MOMIN LOK v. HOSPITAL AUTHORITY

CACV 236/2020

[2021] HKCA 1075

IN THE HIGH COURT OF THE

HONG KONG SPECIAL ADMINISTRATIVE REGION

COURT OF APPEAL

CIVIL APPEAL NO 236 OF 2020

(ON APPEAL FROM HCPI NO 981 OF 2014)

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J U D G M E N T

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Hon G Lam JA (giving the Judgment of the Court):

A.   Introduction

1.  The plaintiff suffered a stroke on 5 December 2008.  She brought the action below against the defendant on 26 September 2014 for damages for that injury which she alleges was the result of negligence of the doctors employed by the defendant in their treatment of her between 16 July and 5 December 2008.  On a trial of preliminary issues, in his judgment of 4 June 2020 (“Judgment”), Bharwaney J found that the plaintiff did not have the requisite knowledge to start time running under section 27 of the Limitation Ordinance (Cap 347) (“Ordinance”) until within 3 years prior to the issue of the writ, and the action had therefore been brought within time.  He further stated that if the action were time‑barred, he would have exercised the court’s power under section 30 of the Ordinance to override the time limit and allow the action to proceed.  The defendant now appeals to this court challenging both of those conclusions.

B.   Background facts

2.  We set out the facts as follows, adopting the judge’s account with modifications.

Right Brachial Artery Occlusion

3.  The plaintiff is a lady of Indian ethnicity born in South Africa in 1973.  In 1992, at the age of 19, she married Mr Lok in South Africa.  As he was a Hong Kong resident, they moved to Hong Kong at the end of 1992.  After moving here, she worked as a kindergarten teacher and a yoga teacher.  She gave birth to 3 daughters. Afterwards, she began taking a combined oral contraceptive pill called Nordette on a regular basis.  By July 2008, she had been on Nordette for 9 years.  A side effect of Nordette is that it increases the risk of thromboembolism in the arterial and venous system.  Venous thromboembolism is a condition in which blood clots are formed in the deep veins, travel in the blood stream, and cause blood vessel obstruction in other parts of the body.

4.  In May 2008, the plaintiff experienced a feeling of coldness in her right arm and hand.  She consulted a general practitioner who diagnosed carpel tunnel syndrome.  She then departed for India, as planned, for an advanced yoga course.  Shortly after arriving in India, she had pain, numbness, and coldness in her right arm and hand.  She attended a local hospital and, after various tests, the doctor found bilateral cervical ribs, causing compression of the right subclavian artery and damped distal flow, and a large echogenic thrombus (a blood clot in a blood vessel) in the chief artery of the right upper arm (brachial artery).  She was advised to return to Hong Kong immediately for an operation to remove the thrombus.  Following that advice, she returned to Hong Kong on 16 July 2008. She was taken to Princess Margaret Hospital (“PMH”) by ambulance from the airport.

5.  At PMH, she presented with right hand acute pain, numbness and coldness, with absence of pulse in her right brachial artery and right radial artery (the chief artery in the forearm).  CT angiogram of her right upper limb showed right brachial artery occlusion (blockage).  Emergency right brachial artery embolectomy (surgical removal of the blood clot) was performed on the same day.

Anticoagulant Therapy & Discovery of Forearm Artery Occlusion

6.  Her treating doctors at PMH had started anticoagulation therapy before the operation, with a continuous intravenous infusion of a blood thinning drug, heparin, which was continued after the operation.  On the next day, 17 July 2008, the plaintiff was started on an oral anticoagulant, warfarin, with a view to long term anticoagulation.  On 18 July 2008, a routine ultrasound scan of the plaintiff’s right arm showed reduced flow in her forearm arteries, and an angiogram revealed occlusion of her forearm arteries (the radial and ulna arteries).  Warfarin was then stopped and she was put back on heparin.  Her surgeon, Dr Chan, decided to manage her conservatively for a few days.  He found that collateral arteries had developed around her right elbow to feed her right hand, and that she appeared to be asymptomatic with a warm hand.  As her right arm had remained stable and pulses were detectable, Dr Chan decided on 21 July 2008 not to operate on her forearm and warfarin was resumed.

Discovery of PFO and Long Term Warfarin Anticoagulation

7.  Various tests were conducted on 21 and 22 July 2008 to investigate the cause of the thrombosis in her right arm, including 2 echocardiograms.  A trans‑thoracic echocardiogram (“TTE”) was conducted on 21 July 2008, which showed rapid appearance of bubbles in the left atrium after an injection of agitated saline into an arm vein.  A trans‑oesophageal echocardiogram (“TEE”) the following day showed the same result.  Based on these results a diagnosis of patent foramen ovale (“PFO”) was made.  A PFO is a hole in the heart that does not close the way it should after birth.  During fetal development, a small flap‑like opening (the foramen ovale) is present in the wall between the right and left upper chambers of the heart (the atria).  It normally closes during infancy, but when it does not, it becomes a patent foramen ovale.

8.  On 25 July 2008, the plaintiff was transferred to the care of Dr Choy, a cardiologist in the Department of Medicine and Geriatrics at PMH.  The purpose of the transfer was for diagnosis of the possible cause of thromboembolism and for supervision of the anticoagulation treatment.  Various tests were conducted including duplex ultrasound of bilateral lower limb but it revealed no deep vein thrombosis.  She continued to take warfarin as prescribed by Dr Choy except for the period from 4 to 12 August 2008 when warfarin was suspended to facilitate control of a haematoma at the right elbow surgical wound.  The plaintiff was discharged home on 6 August 2008, but received outpatient care at PMH for maintenance of anticoagulation, up until the time she suffered a stroke on 5 December 2008.

Another Right Brachial Artery Occlusion

9.  The symptoms of pain, numbness, and coldness in the plaintiff’s right arm and hand recurred and were reported to Dr Chan at a surgical follow‑up on 3 October 2008.  An angiogram taken on 13 October 2008 revealed obstruction of her right brachial artery, and she was immediately re‑admitted to PMH.  Warfarin was suspended from 8 October pending a proposed open exploration.  However, the surgery was not carried out because the symptoms resolved spontaneously, and warfarin was resumed on 31 October 2008.

10.  The plaintiff reported intermittent coldness in her right hand to Dr Chan at a follow‑up on 14 November 2008.  They discussed the possibility of surgery, including an arterial reconstruction.  Surgery was planned for 17 December 2008.

The Stroke

11.  On 5 December 2008, whilst walking from home to work, the plaintiff suddenly felt very sick.  Two passers‑by helped her reach a nearby MTR station, from where she was taken to Tuen Mun Hospital (“TMH”) by ambulance.

12.  She was diagnosed to have suffered an ischaemic stroke (a stroke caused by blockage or obstruction of arteries in the brain), leading to permanent brain damage in her right cerebral hemisphere, resulting in left hemiplegia, with left side motor limb weakness, left facial weakness and slurred speech.  An MRI on 6 December 2008 revealed thrombosis of right internal carotid artery (“ICA”), and middle cerebral artery (“MCA”) with acute infarct (permanent tissue damage due to interruption of blood supply) over the right basal ganglia, the right corona radiata, and the medial right temporal lobe.  A cerebral angiogram on 9 December 2009 showed complete occlusion of a number of arteries in her right cerebral hemisphere, namely, the ICA, the MCA, and the anterior cerebral artery.  After hospitalization for over a month at TMH, the plaintiff was discharged home on 14 January 2009.

13.  After the stroke she became dependent on her husband.  She could walk with a stick, with difficulty, and required help.  She had to be looked after by Mr Lok, who assisted her in her activities of daily living.  The family lived on social welfare as the plaintiff could no longer work and her husband also had to give up his job as a construction inspector in order to look after her and the children.

The plaintiff’s belief

14.  At that time and for some years afterwards the plaintiff believed that her stroke was caused by the prescription of warfarin rather than heparin.  She and Mr Lok consulted a firm of solicitors, Messrs Lee & So, in about August 2010, who submitted an application for legal aid on her behalf on 13 August 2010 to pursue a claim for damages for medical negligence.  The plaintiff also gave a written statement, perhaps with the help of Lee & So, which, among other things, set out her complaints against the doctors.  That statement was not before us but the allegations contained in it can be seen from the expert reports (especially that of Dr Elaine Chau, which quoted and responded to them in turn) subsequently obtained by the Director of Legal Aid (“DLA”).

15.  The plaintiff’s allegations at that time were:

“ (a) Negligently diagnosing me to have suffered from PFO

(b) Negligently prescribing Warfarin to me on the basis that I had been suffering from PFO

(c) Failing to diagnose that my thrombosis might be a side effect of my taking of Nordette, and therefore, the course of treatment should not be based upon PFO

(d) Negligently transferring me from the vascular ward to the Cardiac ward because the incompetent doctor’s failure to take blood from me after 30 attempts

(e) Knowing that I should not have been prescribed warfarin at all or even if I should be prescribed warfarin the dosage had not been of correct amount

(f) Negligently diagnosing the thinness or thickness level of my blood

(g) Failing to diagnose the presence of blood clot in my blood vessels as such blood clot was the cause of the stroke

(h) Failing to explain to me the risks and side effects in association with the prescription of warfarin

(i) Negligently prescribing warfarin to me knowing that I should not take the warfarin because I had a recent operation

(j) Failing to take notice of the ‘patient information leaflet’ of the warfarin that ‘Do not take these tablets (warfarin) if you have had an operation recently’

(k) Failing to warn me about the risks and side effects in association with the prescription of warfarin

(l) Failing to warn the possibility of having a stroke in association with the taking of warfarin”

Expert reports of Dr Yu and Dr Chau

16.  Apart from obtaining medical records and reports from both PMH and TMH, DLA also obtained 2 expert reports from Dr Yu Yuk Ling (a neurologist) (“Dr Yu”) and Dr Elaine Chau (a cardiologist) (“Dr Chau”) respectively in order to evaluate the plaintiff’s application.

17.  In his medical report dated 6 April 2011, Dr Yu expressed the view that the plaintiff was properly treated with warfarin given her Nordette-taking history, her embolic episode and the finding of PFO, and that her ischaemic stroke could not have been caused by warfarin, which is associated with haemorrhagic strokes, not ischaemic strokes.  If she had not been on warfarin, her stroke would have been more severe.  He concluded that the plaintiff’s surgical management of her right brachial artery thrombosis was of high standard; that thrombectomy was promptly performed on the day of admission; and that the investigation of the underlying cause of the plaintiff’s arterial thrombosis was thorough.  If there was PFO, which should be assessed by a cardiologist, warfarin should be prescribed for prevention of further episodes of arterial thrombosis; if there was no PFO, Nordette might be implicated as a causative or contributory factor and warfarin would still be indicated for about 6 months for prophylaxis against further thrombotic episodes.  The plaintiff’s stroke was due to thrombosis of the right ICA and right MCA and was not a complication of warfarin.

18.  In view of Dr Yu’s suggestion of consulting a cardiologist to comment on the diagnosis of PFO, DLA sought an opinion from Dr Chau.  In her medical report dated 13 June 2011, Dr Chau expressed the view that warfarin was the correct treatment for thrombosis, whether or not there was a PFO, that the prescription of warfarin, which increases the risk of bleeding, did not result in the plaintiff’s ischaemic stroke and, if anything, would only have reduced the severity of the stroke.  Despite anticoagulation, the plaintiff sustained an ischaemic stoke due to thrombosis of the right ICA and right MCA.  Dr Chau noted that, following discharge from hospital, the plaintiff was followed up frequently for monitoring of International Normalised Ratio (“INR”) (a measure of the clotting tendency of blood) and adjustment of warfarin dosage according to the plaintiff’s clinical situation.  Such close monitoring of patients on warfarin was the proper standard practice.  On a follow‑up visit on 28 November 2008, the plaintiff’s INR was 1.3 and, therefore, the dose of warfarin was increased from 6 mg per day to 7 mg per day.  On 4 December 2008, the day before the plaintiff was due for follow‑up, the INR was 1.6.  In her opinion, the treatment, diagnosis, and examination given by the doctors at PMH were proper and acceptable from a medical point of view.

19.  On the basis of these 2 expert reports, DLA refused the plaintiff’s application for legal aid on 17 June 2011.

Retaining Ho Tse Wai & Partners and issuing a writ

20.  Meanwhile, the plaintiff and Mr Lok also learned that Mr Albert Ho, a member of the Legislative Council, ran an advice clinic at a community hall at Tuen Mun.  After approaching him sometime in 2011, they were introduced to his solicitors’ firm, Messrs Ho Tse Wai & Partners (“HTW”).  Mr John Clancey and Ms Jasmine Chau of HTW became responsible for handling the plaintiff’s case.

21.  The plaintiff received advice from HTW, as can be seen from her evidence during her cross examination:

“ Q. And he gave you legal advice that, given what you’d said, you should bring proceedings against the Hospital Authority? You should issue a writ?

A. That’s when I went to his offices to -- and approached them, yes, that’s exactly what I was told.

Q. He heard your explanation...

A. My story.

Q. … your story and he said that you should sue the Hospital Authority?

A. He didn’t use the words, ‘You go and sue somebody’.

Q. No.

A. He says, ‘You have a legal case against that, so you can approach this.’  It’s not a matter of sue somebody.”

HTW wrote to DLA on 6 May 2011 that the plaintiff had a possible claim for medical negligence and that it was necessary to obtain an expert report from an experienced vascular surgeon.  The advice she received that “she had a legal case against” the Hospital Authority was likely to have been given at about this time.

22.  The plaintiff lodged an appeal against refusal of legal aid on 23 June 2011.  The appeal was originally fixed to be heard on 8 July 2011, but at the plaintiff’s request it was adjourned to 6 January 2012.

23.  As the plaintiff was first admitted into PMH on 16 July 2008, HTW were aware that a writ should be issued by July 2011, within 3 years.  On 8 July 2011, a writ was issued by the plaintiff against the defendant in the District Court, commencing the action DCPI 1373 of 2011 (“the District Court action”). The general indorsement read as follows:

“ The Plaintiff, claims damages for injury, loss and damage sustained as a result of the negligence and/or breach of duty of the Defendant, its servants, employees or agents in their negligent treatment of the Plaintiff, deceased[1] between 16 July 2008 and 5 December 2008 at Princess Margaret Hospital, which is managed and controlled by the Defendant under the Hospital Authority Ordinance, Cap. 113, and interest thereon and costs.”

The writ was filed by the plaintiff in person. Although HTW assisted her in preparing it, they did not formally act for her, presumably because she had not yet secured legal aid.

24.  In September 2011, the plaintiff, Mr Lok and their 2 younger daughters all went to South Africa to facilitate the plaintiff’s rehabilitation, as she could be better taken care of by her family members in South Africa.

Expert report of Ms Hands

25.  An expert opinion was later obtained by HTW from a vascular surgeon in England, Ms Linda Hands.  In her report dated 25 October 2011, Ms Hands was of the opinion that the surgeons at PMH acted correctly in removing the thrombus on 16 July 2008 but failed to diagnose and treat the underlying cause.  She considered that the plaintiff’s right arm arterial thrombosis was caused by her bilateral cervical ribs compressing on her right subclavian artery which supplies blood to the right arm, and appropriate treatment would have been to remove the cervical rib, either at the time of the thrombectomy or after a short period of anticoagulation, and to repair the dilated artery if necessary.  Ms Hands pointed out that, since the plaintiff’s treating doctors at PMH were of the view that she had a PFO and that her right arm embolus was caused by a paradoxical embolus passing through the PFO, her warfarin therapy was grossly inadequate, “with 1 mg increases in warfarin over one to three week periods and an INR which resolutely failed to rise above a maximum of 1.8 on 3/8/08”.  She took the view that the investigations performed to find a cause for the arm ischaemia were adequate apart from the failure to image the arm arteries in abduction at an early stage.  She did not think that heparin should have been used instead of warfarin after the operation.  She concluded her report as follows:

“ In my opinion the initial surgery performed on Ms Lok’s right arm on 16.07.08 was inadequate. The postoperative management of anticoagulation, formally taken over by the cardiologists, was grossly inadequate and the vascular surgeon’s response to recurrent symptoms and progression of the disease lacked the appropriate speed. If Ms Lok had had appropriate initial treatment she would not have required prolonged anticoagulation and should have had normal arm function maintained. I cannot see a link between the arm arterial thrombosis and Ms Lok’s subsequent stroke, particularly as a central source of embolus in the heart and paradoxical embolism appear to have been excluded.”

It can be seen that, whilst critical of the treatment in certain respects, Ms Hands’ report did not support any causal link between the inadequacies she identified and the stroke.

26.  Following Ms Hands’ report, Mr Clancey and the plaintiff had a telephone conversation with regard to the report.  On 25 November 2011 a copy of the report was emailed by HTW to the plaintiff.  On 29 November 2011, following a meeting with a neurological expert in Hong Kong, HTW advised the plaintiff by email that Ms Hands referred to several areas of negligence but said there was no connection of the negligence to the stroke.  But according to the neurologist there was literature which confirmed that the compression of the subclavian artery could cause a stroke.  HTW wrote: “Therefore the failure to deal with the underlying cause could very well have caused the stroke”, and advised the plaintiff to seek an expert report from the neurologist.

27.  For reasons that are not clear, HTW did not send a copy of Ms Hands’ report to DLA for their consideration or in support of the plaintiff’s legal aid appeal. 

Steps taken to obtain further expert opinion

28.  On 2 December 2011, HTW asked on the plaintiff’s behalf for a further adjournment of the legal aid appeal pending an expert report on causation to be obtained, but were informed that no hearing date had in fact been fixed for the appeal.

29.  Instead, a checklist review hearing for the District Court action was coming up.  HTW assisted the plaintiff in preparing a letter dated 15 December 2011 which she issued to the Master at the District Court, stating:

“ The Writ of Summons … was issued to protect my interest for initiating legal proceedings against the Defendant within the three year limitation period.”

She also stated that the writ had not been served, and asked for an adjournment of the checklist review hearing to a date in March 2012 to allow her time to obtain an expert report in support of her claim.

30.  As Mr Lok could not obtain employment in South Africa, he returned to Hong Kong in early 2012, so that he could obtain work here and help to support the plaintiff and their daughters.

31.  Another letter, signed by Mr Lok on behalf of the plaintiff, similar to the letter of 15 December 2011, was sent to the District Court on about 12 March 2012, asking for a further adjournment of the checklist review hearing scheduled for the following day.

32.  In May 2012, HTW instructed Dr Huang Chen Ya, a neurologist, to advise further on the plaintiff’s case.  Dr Huang advised by telephone on 7 May 2012 that he did not think the plaintiff had a case for the stroke and that it was difficult to make a good case.  Afterwards, HTW wrote to Dr Huang again on 17 May 2012:

“ …

We apologise for troubling you again, but our client is of the view that there is still a possibility that the negligence of the treating doctors had caused damage to her.

… We write to ask whether given the problem with our client’s arm, namely long segment of obstruction at right brachial artery, the fact that our client was still taking warfarin had caused her to suffer from a stroke.

Given our client’s condition at that time, if you are of the view that prescribing warfarin to Mrs Lok was below the expected standard and caused the stroke, we will [formally] instruct you [to] prepare an expert report on liability and causation.”

On 8 June 2012, Dr Huang advised orally that one could not prescribe heparin for a long time and if heparin was stopped, one would need to prescribe warfarin (though aspirin was also a possibility).  As recorded in Mr Clancey’s notes, Dr Huang advised that it was hard to say there was negligence, that there was no sufficiently strong case to proceed, that there was no evidence the arm problem caused the stroke, and that there was no real chance of winning.

33.  Thereafter, HTW asked the plaintiff to seek expert medical opinion from doctors in South Africa in support of her claim.  She did try but was not successful.

34.  In June 2012 HTW went on record for the plaintiff in the District Court action and made an application for the extension of the validity of the writ.  The Master extended it for 6 months. 

35.  At the request of HTW, the plaintiff returned to Hong Kong in December 2012 for the purposes of obtaining a further extension of the writ.  She had a meeting with Mr Clancey.  The notes show that she still considered the doctors should not have prescribed warfarin with her condition.  She made an affirmation seeking a further extension of the writ for 6 months to allow time to obtain a further report on causation.  She attached a very brief letter from Dr van Heerden, a South African doctor, dated 8 December 2012 which stated that more tests needed to be done to ascertain the cause of the stroke.  The Master granted another extension to 6 July 2013.

Discontinuance of the District Court action

36.  By June 2013, the plaintiff had still not been able to find any expert who could give a favourable opinion.  HTW told Mr Lok that they did not have enough evidence.  They gave him a document addressed to HTW to be signed by the plaintiff stating:

“ As I cannot obtain an expert report from an expert in South Africa in support of my claim and as I have no money to continue the Action, I hereby instruct you not to continue with this Action.”

Mr Lok’s evidence, which the judge seems to have accepted, was that he signed the plaintiff’s name on the piece of paper and gave it back to HTW, without informing the plaintiff, because Mr Clancey told him that the case could not go ahead as there was not enough evidence to support her claim.  The judge held that the plaintiff had given Mr Lok authority to deal with HTW in connection with the District Court action including the authority to sign on her behalf to discontinue the action, and that the plaintiff was imputed with the knowledge of such discontinuance and with Mr Lok’s knowledge that the case could not go ahead as “there was not enough evidence to support the claim”.[2]

37.  HTW filed a notice to discontinue the District Court action on 10 June 2013. 

38.  The legal aid appeal was not proceeded with.  DLA contacted HTW in September 2013 who stated that they no longer acted for the plaintiff.  After DLA’s attempts to contact the plaintiff were unsuccessful, the legal aid file was closed in October 2013.  

Second legal aid application and second writ

39.  In late January 2014 the plaintiff returned to Hong Kong from South Africa.  She learnt that the District Court action had been discontinued.  She then took hold of the papers and approached the Legal Aid Department and explained her situation.  On 13 February 2014, a second legal aid application was formally made by her to pursue her claim against the defendant, and she also supplied Ms Hands’ expert report to DLA.  Based on that report, and notwithstanding that it did not demonstrate a causal link with the stroke, legal aid was granted to the plaintiff on 25 July 2014 to pursue the claim and Mr Millar of Messrs Littlewoods was assigned to act as the plaintiff’s solicitor.

40.  Meanwhile, the plaintiff and Mr Lok had drifted apart and were eventually divorced by decree absolute on 26 September 2014, although they remained friendly.

41.  The writ in the High Court was issued by the plaintiff, through Littlewoods, on 26 September 2014 with a general indorsement.  Pursuant to Littlewoods’ enquiry, on 31 October 2014 Ms Hands produced an addendum to her original report, reiterating her opinion that the lack of proper care of the plaintiff’s arm was unlikely to have had any impact on the subsequent stroke.  The writ was served on the defendant on 17 September 2015.

Further medical reports

42.  On 22 January 2016, Dr John Caplin, a cardiologist in England instructed by Littlewoods, provided his first expert report.  He subsequently issued three supplementary reports dated 9 and 23 February and 18 March 2016 respectively.  His opinion was that the TTE and TEE conducted on 21 and 22 July 2008, in conjunction with other findings, show that the plaintiff had significant right‑to‑left shunting that was more suggestive of a pulmonary arterio‑venous malformation (“PAVM”) (ie a right‑to‑left shunt between the pulmonary artery and vein) than a PFO.  PAVM is also associated with a significant risk of embolic stroke through paradoxical embolism.  On balance her brachial artery embolism in July 2008 was due to a paradoxical embolism (a blood clot passing from a vein to an archery) through the shunting.  A responsible body of cardiologists faced with a patient with a brachial embolism and evidence of significant shunting would recommend long-term anticoagulation with warfarin with a target INR of 2.5.  If this had occurred with optimal INR level of greater than 2.0, on balance the plaintiff would have avoided her stroke.

43.  An expert report dated 29 January 2016 was also obtained from Dr Pieter Pretorius, a radiologist in England, who opined that the CT scan performed on the plaintiff on 16 July 2008 shows thrombosis within distended right sided uterine vein, ie pelvic deep venous thrombosis, which was not detected by the radiologist who reported the scan.  This condition represents a significant risk since it can lead to thromboembolism and, in the case of people with PFO, to paradoxical embolism.  The plaintiff’s right brachial artery occlusion and the subsequent stroke were most likely due to paradoxical embolisation of thrombus that originated as deep venous thrombosis in the pelvic veins.

44.  A haematologist in England, Dr Samuel Machin, was also instructed by Littlewoods and gave his report on 22 February 2016.  His opinion was that the overall therapeutic range of INR for a patient on long‑term oral warfarin therapy is 2.0 – 4.5.  The plaintiff should have had a stable therapeutic INR of 2.0 – 3.0 and at a minimum an INR within that range on 50% of follow‑up visits, to be achieved by prescribing oral warfarin and regular monitoring of her INR.  The plaintiff, whose INR was for the most time below 1.5, never obtained the desired INR range.  She was never adequately anticoagulated with warfarin from 21 July 2008 to the time of her stroke (except for 25 July to 4 August when she received injections of LMW heparin, Enoxaparin), and was at a considerable risk of developing an extension and/or embolisation from her pelvic deep vein thrombosis.

Action against HTW

45.  On 16 October 2017, the plaintiff issued a writ in the High Court (HCA 2383/2017) against HTW alleging negligence and breach of contract between 2011 and 2013 in their handling of the plaintiff’s claim arising out of the stroke in 2008, and claiming damages.

C.   The proceedings

46.  In the statement of claim, filed on 28 October 2016, the particulars of negligence are pleaded as follows, essentially reflecting the new expert medical opinions obtained in 2016:

“ 24. The Plaintiff avers that the stroke she sustained and the disability arising therefrom was caused by the negligent actions and omissions of the Defendant, its servants and agents, for whom it is vicariously liable.

PARTICULARS OF NEGLIGENCE

(a) Failing to note and report that the CT angiogram of the right upper limb performed on 16^th July 2008 showed the distal portion of the distended right sided uterine vein was un‑opacified over a segment of approximately 2 cm up to the point where it drains into the right internal iliac vein.

(b) In the premises, failing to note and appreciate that this meant it does not contain flowing blood and this appearance was in keeping with thrombus in the vein, a pelvic deep vein thrombosis (DVT), which was a significant risk to the Plaintiff since it could lead to thromboembolism.

(c) Failing to remove the pelvic deep vein thrombosis.

(d) After the thrombectomy on 16^th July 2008 when the treatment plan of long term anti‑coagulation was established, failing to ensure that from 6^th August 2008 to 5^th December 2008 the Plaintiff was adequately anti‑coagulated, particularly, failing to give her a loading dose of oral warfarin of between 4‑7 mg daily for several days, with regular monitoring of her INR level every 3‑4 days to ensure it was maintained at a level between 2.0 to 3.0.

(e) In the presence of significant right to left shunting shown in the TTE and TEE performed in July 2008, failing to appreciate the risk of further paradoxical embolization in the circumstances of the Plaintiff’s medical history, including the episode of thrombosis in the right brachial artery.

(f) In the light of the fact she was on the combined oral contraceptive pill, failing to guard against the increased relative risk of the Plaintiff developing venous thromboembolism and so ensuring that she was adequately anti‑coagulated as aforesaid.

(g) If the diagnosis in July 2008 of PFO was correct, failing to ensure the Plaintiff was thereafter adequately anti‑coagulated as aforesaid.

(h) Failing to appreciate that the timing of the micro‑bubbles appearing in the left atrium as seen in the TTE and TEE imaging in July 2008 was unusual for PFO and was more consistent with a down‑stream shunt, such as a pulmonary arterio‑venous malformation, and that this also gives rise to the risk of paradoxical embolization and stroke.”

47.  The defendant filed a defence on 9 January 2017 in which a limitation defence is raised but paragraph 24 of the statement of claim is simply not admitted.  It is pleaded that the defendant’s staff involved did not have any or had very limited recollection of the matter and were wholly or very substantially reliant upon contemporaneous records and their routine practices at the time, and that in light of the circumstances the defendant is unable to advance a positive case in answer to the claim.  The defendant also has not filed any expert report in the proceedings whether for the purposes of the preliminary issues or otherwise.

48.  The plaintiff’s summons that led to the preliminary issues was first issued on 24 March 2016, before the statement of claim.  It was at first an application solely for an order under section 30 of the Ordinance that the action be allowed to proceed notwithstanding section 27. It was amended with leave of the judge on 20 June 2017 to seek, in the alternative, a finding that the writ was issued within 3 years of the plaintiff’s date of knowledge under section 27(4)(b).  On the same date the judge ordered that the application be dealt with by way of preliminary issues.  The judge heard evidence from the plaintiff and Mr Lok in two hearings in May 2018 and September 2019 respectively.

D.   The legislative framework

49.  In Hong Kong, many legal actions are subject to statutes of limitation that require them to be brought within a prescribed time.  For actions based on contract or tort, the general time limit is 6 years from the accrual of the cause of action (see section 4 of the Ordinance). Actions for damages for personal injuries resulting from negligence, nuisance or breach of duty are, however, subject to a special time limit provided in section 27, namely, 3 years from the accrual of the cause of action or from “the date (if later) of the plaintiff’s knowledge”.  This provision was the Legislature’s response to the injustice, exemplified by Cartledge v E Jopling & Sons Ltd [1963] AC 758, where personal injury occurred, and the cause of action accrued, to a person who did not realise that he had suffered an injury, let alone that it had been caused by someone else against whom he might have a legal remedy, until after the expiration of the ordinary 6‑year limitation period.

50.  The initial attempt at law reform in Hong Kong was section 27 of the Ordinance, first enacted in 1965.  The Limitation Ordinance 1965 was a comprehensive piece of legislation, based on the Limitation Act 1939 of the United Kingdom (including its subsequent amendments), replacing various old imperial enactments on limitation before 1843, which had been repealed in England but which had force of law in Hong Kong by virtue of section 5 of the Supreme Court Ordinance.  Section 27 of the 1965 Ordinance was modelled on the equivalent reform in England and Wales introduced by the Limitation Act 1963, which was, however, soon found there to be confusing and unsatisfactory (see Smith v Central Asbestos Co Ltd [1973] AC 518 at 529F where Lord Reid that it had “a strong claim to the distinction of being the worst drafted Act on the statute book”).  The law was changed again in England and Wales following the recommendations of the Law Reform Committee in 1974 (20^th Report: Interim Report on Limitation of Actions: in Personal Injury Claims (Cmnd 5630)) when the equivalent of the present section 27 of the Ordinance was enacted by the Limitation (Amendment) Act 1975, later consolidated as sections 11 and 14 of the Limitation Act 1980.  Hong Kong followed suit in 1976 by replacing the old sections 27‑33 with sections 27‑30 in their present form through the Limitation (Amendment) Ordinance (Ordinance No 67 of 1976).[3]

51.  Section 27 of the Ordinance provides as follows:

“ 27. Time limit for personal injuries

(1) This section applies to any action for damages for negligence, nuisance or breach of duty (whether the duty exists by virtue of a contract or of provision made by or under an Ordinance or imperial enactment or independently of any contract or any such provision) where the damages claimed by the plaintiff for the negligence, nuisance or breach of duty consist of or include damages in respect of personal injuries to the plaintiff or any other person.

(2) Section 4 shall not apply to an action to which this section applies.

(3) Subject to section 30, an action to which this section applies shall not be brought after the expiration of the period specified in subsections (4) and (5).

(4) Except where subsection (5) applies, the said period is 3 years from—

(a) the date on which the cause of action accrued; or

(b) the date (if later) of the plaintiff’s knowledge.

(5) ……

(6) In this section, and in section 28, references to a person’s date of knowledge are references to the date on which he first had knowledge of the following facts—

(a) that the injury in question was significant; and

(b) that that injury was attributable in whole or in part to the act or omission which is alleged to constitute negligence, nuisance or breach of duty; and

(c) the identity of the defendant; and

(d) if it is alleged that the act or omission was that of a person other than the defendant, the identity of that person and the additional facts supporting the bringing of an action against the defendant,

and knowledge that any acts or omissions did or did not, as a matter of law, involve negligence, nuisance or breach of duty is irrelevant.

(7) For the purposes of this section an injury is significant if the plaintiff would reasonably have considered it sufficiently serious to justify his instituting proceedings for damages against a defendant who did not dispute liability and was able to satisfy a judgment.

(8) For the purposes of this section and section 28 a person’s knowledge includes knowledge which he might reasonably have been expected to acquire—

(a) from facts observable or ascertainable by him; or

(b) from facts ascertainable by him with the help of medical or other appropriate expert advice which it is reasonable for him to seek,

but a person shall not be fixed under this subsection with knowledge of a fact ascertainable only with the help of expert advice so long as he has taken all reasonable steps to obtain (and, where appropriate, to act on) that advice.

(9) …

(10) …”

52.  A provision similar to section 27 may be found in section 31 of the Ordinance dealing with the problem of latent damage in non‑personal injury negligence actions. The requisite knowledge for time to start running is defined in section 31(5) in terms similar to section 27(6) & (7). Section 31 is modelled on a similar provision created by the Latent Damage Act 1986 for England and Wales (now found in section 14A of the Limitation Act 1980).

53.  Also introduced in England and Wales in 1975 pursuant to the Law Reform Committee’s recommendations, and reproduced in Hong Kong in 1976, is a provision that conferred on the court a discretionary power to allow an action brought out of time to proceed notwithstanding.  This became section 33 of the Limitation Act 1980 in England and is found in Hong Kong in section 30 of the Ordinance, which provides:

“ Court’s power to override time limits

(1) If it appears to the court that it would be equitable to allow an action to proceed having regard to the degree to which—

(a) the provisions of section 27 or 28 prejudice the plaintiff or any person whom he represents; and

(b) any decision of the court under this subsection would prejudice the defendant or any person whom he represents,

the court may direct that those provisions shall not apply to the action, or shall not apply to any specified cause of action to which the action relates.

(2) …

(3) In acting under this section the court shall have regard to all the circumstances of the case and in particular to—

(a) the length of, and the reasons for, the delay on the part of the plaintiff;

(b) the extent to which, having regard to the delay, the evidence adduced or likely to be adduced by the plaintiff or the defendant is or is likely to be less cogent than if the action had been brought within the time allowed by section 27 or 28, as the case may be;

(c) the conduct of the defendant after the cause of action arose, including the extent, if any, to which he responded to requests reasonably made by the plaintiff for information or inspection for the purpose of ascertaining facts which were or might be relevant to the plaintiff’s cause of action against the defendant;

(d) the duration of any disability of the plaintiff arising after the date of the accrual of the cause of action;

(e) the extent to which the plaintiff acted promptly and reasonably once he knew whether or not the act or omission of the defendant, to which the injury was attributable, might be capable at that time of giving rise to an action for damages;

(f) the steps, if any taken by the plaintiff to obtain medical, legal or other expert advice and the nature of any such advice he may have received.

…”

E.   Knowledge under section 27(6)(b)

E1.   General approach

54.  The above legislative survey suggests that Hong Kong authorities not only on section 27 but also on section 31, and English authorities on the equivalent sections 11, 14 and 14A of the 1980 Act, will be instructive on the proper approach to the application of section 27. Whilst in the leading authority on section 31, Kensland Realty Ltd v Tai, Tang & Chong (2008) 11 HKCFAR 237, McHugh NPJ expressed the preference “to disregard the dicta with which the equivalents of s. 31 have become encrusted … and apply … the reasonably clear intention of the legislative text”,[4] it is evident from the judgments of the other members of the Court of Final Appeal that the authorities were regarded as containing valuable principles and guidance on the effect of the statutory provisions.  It is, however, necessary to bear in mind, as Bokhary PJ and Power NPJ pointed out,[5] the caution sounded by Lord Walker in Haward v Fawcetts [2006] 1 WLR 682 that “[t]he wide range of claims to which section 14A may extend suggests that general observations made by the court in one type of case may not be directly apposite in a case of another type”.[6]  This caution is all the more relevant when one considers the authorities on one section for the purposes of another section.

55.  Knowledge for the purpose of section 27 means both actual knowledge and constructive or imputed knowledge: section 27(8). The focus in this case is actual knowledge in terms of section 27(6)(b).[7]  The authorities have established that the word “attributable” in that provision means capable of being attributed to; it refers to a real possibility and not a fanciful one; it signifies knowledge that the act or omission is a possible cause of the damage as opposed to a probable one: Halford v Brookes [1991] 1 WLR 428, 433-434; Nash v Eli Lilly & Co [1993] 1 WLR 782, 797‑798; Haward v Fawcetts [2006] 1 WLR 682, §11; Kensland, §§17 & 95.  The final part of section 27(6) makes it clear that the inquiry is not concerned with any knowledge that the act or omission involved negligence or breach of duty: see Kensland, §§86-89.

56.  As to the requisite degree of certainty of the plaintiff’s knowledge, the plaintiff does not have to know for certain and beyond possibility of contradiction.  It means knowing “with sufficient confidence to justify embarking on the preliminaries to the issue of a writ, such as submitting a claim to the proposed defendant, taking legal and other advice and collecting evidence”.  “Suspicion, particularly if it is vague and unsupported, will indeed not be enough, but reasonable belief will normally suffice”: Halford v Brookes, p 443; Haward v Fawcetts, §9; Kensland, §§16, 94‑98.  In AB & others v Ministry of Defence [2013] 1 AC 78, Lord Wilson said he would have preferred the phrase “reasoned belief”;[8] see §62 below.

57.  In Kensland, McHugh NPJ criticised this approach of defining the requisite degree of knowledge by reference to the knowledge that warrants further investigation, suggesting that this stemmed from a confusion between the concept of actual knowledge and constructive knowledge as defined in section 31(7) (the equivalent of section 27(8) in non‑personal injury cases).[9] However, as Ribeiro PJ said in the same case,[10] the answer given in the cases was a pragmatic one: the plaintiff’s knowledge is to be treated as sufficient to set time running from the moment when a reasonable person would have regarded it as certain enough “to justify embarking upon the preliminaries to the making of a claim for compensation such as the taking of legal or other advice”.  This seems to us to be consistent with the purpose of section 27(6), which is to determine the starting point of a period of time within which a plaintiff can be required to institute proceedings.  From that point, he or she has three years to conduct further investigation and bring it to a stage when a writ can be issued.

58.  Section 27(6)(b) refers to knowledge of the injury being attributable to the act or omission alleged to constitute negligence.  In a case such as the present concerning alleged medical negligence, both the acts or omissions and the question of causation may be highly complicated.  This may obviously give rise to the question of the depth of detail a plaintiff needs to know.  In this connection, in Haward v Fawcetts, Lord Nicholls said (at §10):

“ Consistently with the underlying statutory purpose, Slade LJ observed in Wilkinson v Ancliff (BLT) Ltd [1986] 1 WLR 1352, 1365, that it is not necessary for the claimant to have knowledge sufficient to enable his legal advisers to draft a fully and comprehensively particularised statement of claim. Where the complaint is that an employee was exposed to dangerous working conditions and his employer failed to take reasonable and proper steps to protect him it may well be sufficient to set time running if the claimant has ‘broad knowledge’ of these matters. In the clinical negligence case of Hendy v Milton Keynes Health Authority [1992] 3 Med LR 114, 117-118, Blofeld J said a plaintiff may have sufficient knowledge if she appreciates ‘in general terms’ that her problem was capable of being attributed to the operation, even where particular facts of what specifically went wrong or how or where precise error was made is not known to her. In proceedings arising out of the manufacture and sale of the drug Opren Purchas LJ said that what was required was knowledge of the ‘essence’ of the act or omission to which the injury was attributable: Nash v Eli Lilly & Co [1993] 1 WLR 782, 799. In Spargo v North Essex District Health Authority [1997] PIQR P235, P242 Brooke LJ referred to ‘a broad knowledge of the essence’ of the relevant acts or omissions. To the same effect Hoffmann LJ said section 14(1)(b) requires that ‘one should look at the way the plaintiff puts his case, distil what he is complaining about and ask whether he had, in broad terms, knowledge of the facts on which that complaint is based’: Broadley v Guy Clapham & Co [1994] 4 All ER 439, 448.”

59.  The majority of the Court of Final Appeal in Kensland espoused the jurisprudence developed in the English cases.[11]  Thus, Bokhary PJ and Power NPJ referred to the above principles set out by Lord Nicholls in Haward v Fawcetts at §10 as “settled”.[12]  Ribeiro PJ (with whom Chan PJ agreed) likewise referred to that passage in Lord Nicholls’ judgment in Haward v Fawcetts and to similar passages in Hallam‑Eames v Merrett Syndicates Ltd [2001] Lloyd’s Rep PN 178 at 181 with evident approval.[13]  His Lordship said that the section does not require the plaintiff to have knowledge of the “full‑blown pleaded facts”[14] and that what matters is the plaintiff’s knowledge of “what lies at the core of the pleaded case”[15], drawing attention to the guidance offered by Hoffmann LJ in Broadley v Guy Clapham & Co [1994] 4 All ER 439 at 449 as follows:

“ How does one determine the ‘essence’ of the act or omission? The purpose of s 14(1), as Lord Donaldson MR pointed out in Halford v Brookes [1991] 3 All ER 559 at 573, [1991] 1 WLR 428 at 443 is to determine the moment at which the plaintiff knows enough to make it reasonable for him to begin to investigate whether or not he has a case against the defendant. He then has three years in which to conduct his inquiries and, if advised that he has a cause of action, prepare and issue his writ. Ordinarily it will suffice that he knows that the injury was caused by an act or omission of the defendant. But there may be cases in which his knowledge of what the defendant did or did not do is so vague and general that he cannot fairly be expected to know what he should investigate.”

60.  It has been pointed out that this passage refers to the time for the plaintiff to begin to investigate whether he has a case against the defendant having regard to the knowledge of attributability already possessed, not to begin to investigate the question of attributability, though the investigation envisaged may well also embrace a search for evidence relevant to causation: AB v Ministry of Defence, §§12, 118.  It may be that, in a case that raises complex and difficult issues, three years may not be enough for the plaintiff to complete his investigation and issue a writ (see, for example, Sniezek v Bundy (Letchworth) Ltd [2000] PIQR P213), but the remedy for such cases lies in the discretionary power in section 30 to override time limit rather than in characterising the plaintiff as not having the requisite knowledge to start time running.

61.  The principles distilled from the case law were presented by Brooke LJ in Spargo v North Essex District Health Authority [1997] PIQR P235 at P242 in an oft-cited summary as follows:

“ (1) The knowledge required to satisfy section 14(1)(b) is a broad knowledge of the essence of the causally relevant act or omission to which the injury is attributable;

(2) ‘Attributable’ in this context means ‘capable of being attributed to’, in the sense of being a real possibility;

(3) A plaintiff has the requisite knowledge when she knows enough to make it reasonable for her to begin to investigate whether or not she has a case against the defendant. Another way of putting this is to say that she will have such knowledge if she so firmly believes that her condition is capable of being attributed to an act or omission which she can identify (in broad terms) that she goes to a solicitor to seek advice about making a claim for compensation;

(4) On the other hand, she will not have the requisite knowledge if she thinks she knows the acts or omissions she should investigate but in fact is barking up the wrong tree; or if her knowledge of what the defendant did or did not do is so vague or general that she cannot fairly be expected to know what she should investigate; or if her state of mind is such that she thinks her condition is capable of being attributed to the act or omission alleged to constitute negligence, but she is not sure about this, and would need to check with an expert before she could be properly said to know that it was.”

Whilst useful, it should be borne in mind that summaries such as this, however accurate they may be, should not be treated as statutory texts: AB v Ministry of Defence, §68 per Lord Walker; see also §119 per Lord Phillips.

E2.   Reasonable or reasoned belief

62.  The approach that it was sufficient if the plaintiff has a reasonable belief in attributability gave rise to controversy and a deep division of judicial opinion in AB v Ministry of Defence.[16]  The issue arose because the British servicemen there believed they had been injured by radiation from experimental thermonuclear explosions in the 1950s but had no objective basis for their belief until a new scientific study emerged in 2007.  Lord Wilson affirmed the view expressed in Halford v Brookes that a plaintiff is likely to have acquired knowledge of the facts specified in the section when he first came reasonably to believe them, although his Lordship would have preferred the phrase “reasoned belief” to “reasonable belief” as better conveying “the need for the belief not only to be held with a degree of confidence (rather than to be little more than a suspicion) but also to carry a degree of substance (rather than to be the product of caprice)”.  He agreed that the basis of the plaintiff’s belief plays a part in the inquiry, but did not accept that a plaintiff lacks knowledge until he has the evidence with which to substantiate his belief in court.[17]  Lord Walker also considered that evidence to support a claim was not part of the knowledge required.  He affirmed that reasonable belief suffices but added that weight must be given to the belief being “reasonable”.[18]  The majority of the court rejected the minority’s view that belief in attributability had to be founded on known fact if it was to amount to knowledge. 

63.  In our view the decision of the majority in AB v Ministry of Defence is consistent with Kensland.  The majority in Kensland embraced a pragmatic and purposive approach rather than a conceptual one that emphasises the epistemological distinction between knowledge and belief.  Whilst Ribeiro PJ recognised that a reasonable person might refrain from embarking upon the preliminaries to litigation where he only had “speculation or unsubstantiated suspicion”,[19] we do not think that his Lordship intended to suggest that a plaintiff’s belief, however firmly held, must be supported by known facts or evidence before it can amount to knowledge under the statute.  There is no dispute between the parties in this case that the majority’s view of the law in AB v Ministry of Defence is the one that should be applied.

E3.   “Barking up the wrong tree”

64.  In several decided cases, the plaintiff knew he or she had suffered injury, but wrongly believed that it was attributable to certain act or omission that was subsequently found not to be the true cause.  Thus in Driscoll‑Varley v Parkside Health Authority [1991] 2 Med LR 346, the plaintiff had a fracture of the right tibia and fibula and received treatment, but the leg was not set and there was dead bone.  The plaintiff originally thought that the problem was caused by the surgeon’s negligence, but later discovered that the real cause was not the operation but the removal of the leg from traction during subsequent treatment.  Hidden J held that time did not begin to run based on the plaintiff’s initial belief but only after she became aware that the causative act was her premature mobilisation.  In Broadley v Guy Clapham & Co at p 449, Hoffmann LJ described this case as follows:

“ He will also not have reached the starting point if, in an unusual case like Driscoll-Varley v Parkside Health Authority, he thinks he knows the acts and omissions he should investigate but in fact he is barking up the wrong tree.”

65.  The expression “barking up the wrong tree” has been repeated in some later cases, including in Brooke LJ’s summary in Spargo (see §61 above).  It also featured in AB v Ministry of Defence, where the claimants initially alleged that they had been exposed to “prompt radiation” (radiation from gamma rays affecting those close to the explosion) but, at the start of the hearing, confined their case to the effects of radioactive fallout (the exposure to fall‑out of alpha and beta particles which if inhaled or swallowed could remain in the body and produce a cumulative effect).  At first instance, Foskett J held that a belief that the injury was due to prompt radiation would have reflected a significant misconception and would be the equivalent of “barking up the wrong tree” in the sense used in the authorities.[20]  The English Court of Appeal disagreed, but on further appeal to the UK Supreme Court, Lord Walker said: “I respectfully doubt whether the Court of Appeal was right to differ from the judge in his conclusion that the belief of many of the claimants that they had been exposed to prompt radiation was a significant misconception which (had it stood alone) would have amounted to ‘barking up the wrong tree’ ”.[21] In Harrison v Isle of Wight NHS Primary Care Trust [2013] EWHC 442 (QB), a patient who initially thought that she was injured because her surgeon excised an excessive amount of the distal clavicle and a significant amount of the acromion was said to be barking up the wrong tree, since her problem was in fact caused by the deltoid muscle being detached from the acromion bone (see §§49-51).

66.  Obviously, however, it is not every mistake that will prevent time from running.  Just as a plaintiff is only required to know in broad terms the act or omission to which his injury was capable of being attributed, so any mistake must be so fundamental as to mean that he does not even possess knowledge at that level of generality.  Were it to be otherwise a subsequent change in the particulars of a plaintiff’s complaint might be said to be sufficient to start time running again.  It may be noted that in AB v Ministry of Defence,[22]Lord Walker expressed the view that Driscoll‑Varley was “a rather marginal example of barking up the wrong tree, since the plaintiff’s misapprehension was in relation to the causative event in a single course of treatment, although the real complaint was about the after‑care rather than the operation itself”.

E4.   The effect of instituting proceedings

67.  Another point considered in AB v Ministry of Defence that is relevant for present purposes is the significance of the commencement of proceedings.  In that case, Lord Wilson considered it difficult to perceive how in any case where a plaintiff has sought advice and taken proceedings, it can rightly be held that he had not then had relevant knowledge,[23] and that it was “heretical” to suggest that even after his claim was brought, a plaintiff remained in a state of ignorance.[24]  Lord Walker and Lord Brown were of a similar opinion.[25]

68.  These views should however be seen in their context, which was a case in which proceedings had already been begun by certain claimants based on the allegations they wished to continue to pursue.  In our respectful opinion they do not necessarily apply in the same way to, for example, a writ that truly amounted to “barking up the wrong tree” (it may be noted that a prior writ had also been issued in Driscoll‑Varley) or a protective writ issued against multiple persons who the plaintiff thinks may potentially be responsible without any real sense as to what actually caused the injury.  In AB v Ministry of Defence,[26] Lord Mance expressly reserved his opinion in relation to the significance of proceedings issued but no longer pursued, as in Whitfield v North Durham Health Authority [1995] 6 Med LR 32, where Waite LJ said at p 37:

“ The issue of a writ claiming damages for negligence may of course be prompted by knowledge acquired after the fullest investigation and consultation; but it may equally well be the product of a generalized — though as yet unspecifically informed — sense of grievance …”

F.   The plaintiff’s knowledge in this case

69.  As the judge pointed out,[27] there is no question of imputed knowledge in the present case.  Nor is there any dispute that the plaintiff knew the injury was significant and the identity of the defendant and of the persons who committed the relevant acts or omissions, in terms of section 27(6)(a), (c) and (d).  The crucial issue is that arising from section 27(6)(b), as to when the plaintiff first had knowledge that the “injury was attributable in whole or in part to the act or omission which is alleged to constitute negligence”. 

70.  In her affirmation of March 2016, the plaintiff said that she believed her stroke was caused because she was prescribed warfarin rather than heparin.  In oral evidence she admitted that she searched for lawyers to assist her and that she went to see the solicitors Lee & So in August 2010:

“Q. ... You had your own belief that [the stroke] was caused by the treatment you’d had at the hands of the Hospital Authority?

A. Exactly.

Q. And that’s really been your understanding throughout?

A. Yes.

…

Q. And you needed to see a lawyer because you wanted to know about suing the Hospital Authority for the treatment they’d given you?

A. Yes. I wanted to know what went wrong and our how I could be compensated for this.

Q. Absolutely. So just to summarise, you wanted to consult a lawyer to see what had gone wrong in the treatment of you by the Hospital Authority so that you could be compensated for the injuries you’d suffered as a result of that treatment?

A. Exactly.”

71.  The evidence shows that by August 2010 the plaintiff believed that her injury had been caused by the treatment she had received from the defendant.  She knew enough to consult Lee & So, apply for legal aid, and give a statement complaining of the diagnosis and treatment she received at the hands of the defendant.  It included in particular complaints relating to the use of warfarin, the diagnosis of the thickness level of her blood, and the presence of blood clot in her blood vessels (see §15 above).  When DLA wrote to PMH and TMH in September and November 2010 respectively asking for the medical records, the letters referred to the plaintiff’s “potential medical negligence claim”.  In April and June 2011, Dr Yu’s and Dr Chau’s opinions were obtained by DLA based on the plaintiff’s complaint that the stroke was a complication of warfarin, although the opinions were negative. 

72.  In around May 2011 the plaintiff consulted HTW, and Mr Clancey gave her advice that she “[had] a legal case” and should issue proceedings (see §21 above).  In July 2011, she caused the writ to be issued in the District Court action, with a firm belief that her stroke was attributable to the medication and surgery she had from the defendant, as shown in her oral evidence:

“ Q. But you understood what the nature of the claim was?

A. Exactly.

…

Q. And it was for a claim against the Hospital Authority in relation to your treatment from the time you first went in until after you had your stroke, yes?

A. Yes.

Q. And it was in relation to the treatment that you had from the Hospital Authority’s people, their servants, their doctors?

A. Exactly.

Q. And in …

A. The medication.

…

Q. Right. Including the surgery?

A. We always disputed the medication and surgery.

…

Q. And … all aspects of their treatment during the period?

A. Yes. Exactly.”

73.  Admittedly the writ was not served, but this was not because the plaintiff had any doubt she had received wrong treatment causing the stroke, but because she and HTW were trying to obtain a favourable expert opinion to support her claim.  The failure to secure a supportive expert report eventually led to the discontinuance of that action in July 2013 by Mr Lok and HTW on the plaintiff’s behalf.

74.  In our view, on the evidence, well before 26 September 2011 (three years before the writ in the High Court), probably by August 2010 and certainly by July 2011, the plaintiff had the requisite knowledge that her injury was capable of being attributed to the anticoagulation medication and treatment she received from the defendant.  She knew enough for it to be reasonable for her to embark upon the preliminaries to the commencement of proceedings, and in fact embarked upon those steps including obtaining legal advice, gathering medical records and commissioning expert medical opinions, and actually commenced proceedings against the defendant.  Time had started running.  It was unnecessary for her to know in what precise way the anticoagulation treatment was wrong and led to her stroke.  That her new experts who reported in 2016 gave detailed explanation of what (in their opinion) led to the stroke, including a new point that the radiologist at PMH missed the pelvic deep venous thrombosis, did not reset the clock.  That, in our view, would be the type of knowledge necessary for pleading a statement of claim, but not broad knowledge of the essence of her claim required under section 27(6)(b): see Haward v Fawcetts, §10, quoted in §58 above; and Kensland, §§103-107.

75.  Mr Ronald Tang, for the plaintiff, submits that the correct question is: when did the plaintiff come to reasonably believe there was a real possibility that her stroke was caused by inadequate anticoagulation. The answer, he says, is the date of Dr Caplin’s report (22 January 2016) or, alternatively, the date of Ms Hands’ report (25 October 2011).  He emphasises that the plaintiff must have a reasonable or reasoned belief in attributability, citing AB v Ministry of Defence, §§11, 50, 170.  We can understand why he has formulated the question in this way, but it would in our view be too narrow an enquiry.  There is no reason or support in the authorities why a reasonable belief that the injury was caused by the anticoagulation medication and treatment should not suffice.

76.  We recognise that the evidence also shows that the plaintiff not only considered that her stroke was broadly attributable to the anticoagulation treatment, but that she was fixated upon the idea that the stroke had in particular been caused by the doctors prescribing warfarin to her instead of heparin.  It appears that she formed this view from the fact that she was feeling well when on heparin but had unusually severe bleeding during menstruation upon the change of medication to warfarin.

77.  The complaint that she should not have been given warfarin, as the judge observed,[28] was the opposite of what is now pleaded as the causative act or omission, namely, that she was not given enough of it.  The judge thought, relying on McGee, Limitation Periods (8^th ed) at §8.041, that the majority decision in AB v Ministry of Defence was that a plaintiff’s belief that his injury is attributable to the defendant’s act or omission must be “justified by at least some degree of evidence” for time to begin to run.  The judge held that the plaintiff’s belief was “unsupported and unreasonable”, and as such her understanding did not amount to the requisite knowledge.[29]

78.  With respect, it seems to us that the majority in AB v Ministry of Defence actually rejected the approach that time does not run until the plaintiff’s belief in attributability is capable of being supported or justified by evidence.  The claimants’ counsel there conceded that “evidence” was no part of “knowledge” for the purpose of the subsection.[30] While Lord Wilson accepted that the basis of a claimant’s belief plays a part in the inquiry, and apparently agreed with Baroness Hale that an unreasonable belief in attributability does not amount to knowledge, he did not accept that a claimant lacks knowledge until he has the evidence with which to substantiate his belief,[31] and emphasised the “irrelevance of evidence to an enquiry under the subsections”.[32]  Lord Walker also drew a “distinction between knowledge of the ‘essence’ of a claim and the evidence necessary to prove it” whilst observing that there may sometimes be great difficulty in the practical application of that abstract distinction.[33]  Lord Mance stated that the “courts, by using the words ‘reasonable belief’ as part of the description of the requisite knowledge, are focusing not so much on whether or how far the belief is evidence‑based, but more on whether it is held with a sufficient degree of confidence to justify embarking on the preliminaries to making a claim including collecting evidence”.[34]  Lord Brown agreed with the reasons of Lords Wilson, Walker and Mance.[35]  In our view, nothing in the majority judgments shows that the plaintiff’s belief is required to be justified by evidence before he or she may be held to have the requisite knowledge.  The judge erred in directing himself to the contrary.

79.  The plaintiff believed that her injury was attributable to the treatment and, in particular, the medication given to her by the defendant.  This knowledge of the real possibility of causation was enough to justify the taking of the preliminary steps for proceedings, which were in fact undertaken.  The fact that the opinions of Dr Yu, Dr Chau, Ms Hands and Dr Huang did not support the attribution of the stroke to the defendant’s acts or omissions does not in our view negate the plaintiff’s knowledge: see Sniezek v Bundy (Letchworth) Ltd.  The plaintiff herself made it clear in her evidence that she disagreed with those opinions.

80.  The plaintiff had a rational basis for thinking that her stroke was caused by the medication relating to blood coagulation. Her belief was a “reasoned” one, not based on caprice.  She might have been mistaken in her detailed reasoning, since she suffered an ischaemic stroke rather than a haemorrhagic stroke and had she not been given warfarin her stroke might have been more severe.  But this, in our view, does not mean that she did not have a reasonable belief – in the sense of a belief confidently held which carries a degree of substance – in the requisite attributability.

81.  Nor can the plaintiff be treated as not having the requisite knowledge on the ground that she was “barking up the wrong tree” as Mr Tang submits.  She was correct, on the footing of her present case, in thinking that it was wrong treatment on anticoagulation that resulted in the stroke.  It is true that she mistakenly thought that the doctors should have prescribed heparin rather than warfarin, but this misguided belief in the precise manner in which the treatment resulted in injury did not prevent time from running under the statute.  Her misapprehension related to the particulars of the anticoagulation treatment.  If a case such as Driscoll‑Varley was a “rather marginal example” of barking up the wrong tree (see §66 above), it is clear that the plaintiff’s belief in this case was much nearer the correct target.  She was, at most, barking up the wrong branch of the right tree.  The fact that her mistaken belief might have caused her initially to run into a blind alley may be a factor to be considered in the exercise of the discretion under section 30, but is not a reason to conclude that she did not have the requisite knowledge under section 27(6)(b).

82.  For these reasons, we take a different view from the judge and hold that the writ was not issued within three years of the plaintiff’s date of knowledge under section 27.  This brings us to the question of the exercise of discretion under section 30.

G.   Discretion under section 30

G1.   General

83.  Section 30(1), set out in §53 above, empowers the court to order that the provisions of section 27 shall not apply to an action if it appears to the court that it would be equitable to allow the action to proceed.  Section 30(3) sets out six specific matters to which the court must have regard among all the circumstances of the case. 

84.  It is well established that the court’s discretion under section 30 is wide and unfettered: Horton v Sadler [2007] 1 AC 307, at §§9, 17 & 26; Lu Guo Xiang v Hong Kong Ming Wah Shipping Co Ltd [2009] 1 HKLRD 390 at §24.  In choosing between the competing outcomes the court must be guided by what appears to it to be equitable, which means no more and no less than fair: Horton v Sadler at §32 per Lord Bingham.  However, Lord Hoffmann has also said in Horton v Sadler (at §44):

“ since [the decision of the House of Lords in Thompson v Brown [1981] 1 WLR 744] the practice of the courts has been regularly to exercise the discretion in favour of the plaintiff in all cases in which the defendant cannot show that he has been prejudiced by the delay.  No matter how negligent the claimant’s solicitors may have been in the simple skills of keeping a diary, the plea of limitation which the statute confers upon the defendant is, in the absence of forensic prejudice, described as a windfall of which he can properly be deprived.”

This has been accepted by this Court as the settled correct approach: Chuck Wai Man v Asia Television Ltd (CACV 29/2008, 9 September 2008) at §24 per Tang VP.

G2.   The judge’s decision and the defendant’s complaints

85.  The judge, understandably given his conclusion on section 27, dealt with this topic briefly.  He said in §65 of his Judgment: 

“ If I had concluded that this action was time‑barred in that the plaintiff’s belief, which she held shortly after she suffered a stroke, that her treatment by warfarin, instead of heparin, caused the stroke, was sufficient for time to begin to run under LO, I would have exercised my discretion under s 30 of LO to override the time limit. I would have done so on the ground that the plaintiff had acted promptly and had made reasonable efforts to obtain expert medical opinion to support her claim; that the delay was caused by the negative medical opinion she had received; that the plaintiff’s claim did not appear to be weak or of little value; and that the defendant has not demonstrated that it has suffered prejudice from this delay. Specifically, the defendant had received notification of the plaintiff’s claim by DLA’s letters to PMH dated 14 September 2010 and TMH dated 5 November 2010, less than two years after the stroke on 5 December 2008, which would have enabled the defendant to gather and assemble, in good time, all relevant clinical notes and records, test results, scans and reports to enable it to study, investigate and, if so advised, to resist, the plaintiff’s claim.”

86.  On this appeal Mr Nigel Kat SC complains on behalf of the defendant that the judge failed to take into account the District Court action, the plaintiff’s delays, the plaintiff’s action against HTW, the prejudice to the defendant and the likely costs of the proceedings if they continue.

G3.   Discussion

87.  On appeal, the grounds on which this court may interfere with the judge’s exercise of discretion are limited: SPH v SA (2014) 17 HKCFAR 364 at §65; Hadmor Productions Ltd & others v Hamilton & another [1983] 1 AC 191, 220.  We shall deal with the specific points raised by the defendant and in that context the matters enumerated in section 30(3). 

88.  First, Mr Kat emphasises that the plaintiff had started the District Court action but abandoned it before commencing her action in the High Court.  He submits that Horton v Sadler held (at §§16 & 33) that it is contrary to the policy of the statute for a plaintiff to start an action and, after time has expired, knowingly to abandon it only later to start another action outside the limitation period.  We do not think that the case laid down any such categorical rule.  It had been held in Walkley v Precision Forgings Ltd [1979] 1 WLR 606 that the section could not avail such a plaintiff because, having brought a prior action within time, he was not “prejudiced” by the time-bar within the meaning of the section.  This approach was rejected in Horton v Sadler, which held that the discretionary power could be applied in favour of a plaintiff who had issued a prior action within time.  That the court in Horton v Sadler considered that Walkley was correctly decided on its facts simply shows that the discretion is an unfettered one to be exercised on the facts of each case.

89.  In the present case, the decision to discontinue the District Court action was not based on caprice or acceptance of defeat, but was a step taken by Mr Lok on the plaintiff’s behalf under HTW’s advice without any real alternative when the plaintiff had not been able to obtain any favourable expert opinion based on her specific belief of what had resulted in her injury.  That line of investigation was, on the basis of the plaintiff’s present case, mistaken and, whilst not so fundamental as to prevent time from running altogether as explained above, resulted in the plaintiff not being able to find any expert evidence in support.  Moreover, Mr Lok’s evidence was that HTW told him, when he was given the papers for discontinuance, that it was not an absolute end but “simply a temporary stop or suspension”.  The plaintiff herself was in South Africa at the time and not personally aware of the discontinuance until late January 2014 when she came back to Hong Kong.  Although the judge did not refer to the District Court action in §65 of his Judgment, he was clearly aware of it, having referred to it earlier in the Judgment,[36] and probably treated it as part of the plaintiff’s delay complained of by the defendant.

90.  The second matter relied upon by Mr Kat — the plaintiff’s delays particularly from mid‑2011 — is related to the first.  But as noted by the judge, the expert opinions that had been obtained by mid‑2011 from Dr Yu and Dr Chau, based on the plaintiff’s allegations at that time, were negative.  Ms Hands’ report obtained in October 2011 was critical of the defendant but was, crucially, negative on causation.  By then the plaintiff had gone back to South Africa, though she continued, unsuccessfully, to look there for expert opinion in support.  In June 2012 Dr Huang also advised negatively based on the plaintiff’s then allegations.  Throughout these years the plaintiff was under the disabling effects of the stroke, and was between September 2011 and January 2014 residing in South Africa for rehabilitation (except for a short trip to Hong Kong in December 2012).  Her husband had returned to Hong Kong since early 2012 but hardly had a great deal of resources at his disposal.  This seems to us to be an unusual case where pursuant to a wrong line of investigation, the expert opinions successively obtained by the plaintiff were all against her.  In the circumstances we share the Judge’s view that the plaintiff had made reasonable efforts to obtain expert medical opinion to support her claim.  The delay was caused at least in part by the plaintiff’s mistaken belief as to what precisely went wrong and the negative medical opinions received based on that belief.  Mr Kat further criticised the plaintiff for having “sat back and waited” between March 2014 after she applied for legal aid and July 2014 when legal aid was granted, but this period was a short one in the scheme of things and given the circumstances it was not unreasonable for the plaintiff to pin her hopes on a successful legal aid application.

91.  Thirdly, Mr Kat relies on the plaintiff’s extant action against HTW.  We are told that the writ was served but by agreement the action has been put on hold pending the resolution of the present limitation dispute.  We accept that “a plaintiff’s right of full recovery against his negligent solicitor was always a highly relevant consideration in striking the balance”, but it is by no means conclusive: Horton v Sadler at §§17 & 32.  As Lord Bingham said (at §33): “even if the plaintiff had a cast‑iron claim against her solicitors the limitation defence could fairly be regarded as a windfall or gratuitous bonus.  Between these extremes lie a variety of cases turning on different facts”.

92.  The only solicitors’ conduct Mr Kat has mentioned is the fact that HTW did not send Ms Hands’ report to DLA, even though her opinion was that there was no causal link between the inadequate treatment and the stroke.  Beyond that Mr Kat has not pointed to any specific act or omission on HTW’s part which would give rise to any ground for complaint, let alone a “right of full recovery” or a “cast‑iron claim” for the plaintiff.  We refrain from commenting on the merits of that action but it is obviously very different from a case where the solicitors lacked the simple skills of keeping a diary and negligently allowed time to lapse without issuing a writ.  In that action the plaintiff would have to prove negligence on the part of HTW, and that it caused a loss of a chance of obtaining damages from the Hospital Authority, which would still necessitate an investigation into the merits of her claim for medical negligence.

93.  Fourthly, Mr Kat says there is prejudice to the defendant if the limitation period is disapplied.  There is a general assertion that the defendant’s ability to defend has been adversely affected by the delay in the prosecution of the case but we note that the defendant did not adduce any specific or concrete evidence in this regard.  On the defendant’s case, the plaintiff had the requisite knowledge in August 2010 or July 2011, and could therefore have brought an action within time up to August 2013 or July 2014, which would already be five or six years after the events.  The relative lateness of the present action which was brought in September 2014 has to be seen in this context.  There is no evidence regarding the cogency of the treating doctors’ evidence in terms of section 30(3)(b) with reference to this timeframe even in the affidavits of the treating doctors made in 2017 which were eventually not produced at the hearing below.  The judge’s conclusion that the defendant had not demonstrated that it had suffered prejudice from the delay cannot, in our view, be faulted.

94.  It is also relevant to take into account, as the judge did, that the defendant had received notification of the plaintiff’s “potential medical negligence claim” by DLA’s letters to PMH dated 14 September 2010 and to TMH dated 5 November 2010, less than two years after the stroke, which would have enabled the defendant to gather and assemble all relevant clinical notes and records relevant to the plaintiff’s claim.  There is no suggestion that any records had been lost.

95.  Fifthly, Mr Kat refers to the costs of the proceedings if they continue, submitting that the parties, both on public funds, will have to incur much time and resources.  We do not think this alters the balance.  The judge said that the plaintiff’s claim did not appear to be weak or of little value, and Mr Kat has not gainsaid that.

96.  In our view, it may be said that there is ground for re‑opening the question of discretion because it does not appear that the judge took into account the action against HTW, which was a relevant factor but not mentioned at all in the Judgment.  But this does not affect the outcome because in all the circumstances of the case, and having regard to the matters discussed above, we too consider that it would be equitable to allow the action to continue and would exercise the discretion in the same way.

H.   Conclusion and disposition

97.  For the above reasons, we differ from the judge on the question as to when the plaintiff had the requisite knowledge of attributability under section 27(6)(b).  Accordingly, we set aside the judge’s judgment to the contrary.  However, we exercise the discretion to disapply the time limit in the same way as the judge and therefore make an order under section 30 that the provisions of section 27 shall not apply to the action.

98.  We propose to deal with costs on the basis of written submissions, to be lodged by the plaintiff within 14 days and by the defendant within 7 days thereafter, followed by a reply by the plaintiff within 7 days thereafter.