LAW CHUNG FAI v. LAM MING KUEN

HCPI 96/2008

IN THE HIGH COURT OF THE

HONG KONG SPECIAL ADMINISTRATIVE REGION

COURT OF FIRST INSTANCE

PERSONAL INJURIES ACTION NO. 96 OF 2008

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DECISION

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1.  This is an application by the defendant to change his medical liability expert.

2.  These proceedings were brought by the next friend of Mr Law Chung Fai claiming damages for personal injuries from the defendant, a qualified medical practitioner practising as a specialist in neurosurgery in Hong Kong.  The plaintiff was admitted to St Theresa’s Hospital on 28 May 2006 after suffering from headaches, dizziness and confusion for about one week.  MRI and MRA examinations performed on that day confirmed the presence of a small arteriovenous malformation (“AVM”) associated with a recent haemorrhage in the posterior left temporal lobe of the plaintiff.  The defendant was consulted and, after discussion in the presence of family members, a decision was made for early intervention and micro-surgical excision.  This was carried out on 29 May 2006.  This operation was described as a straight-forward and, according to the defendant, the plaintiff woke up as expected after general anaesthesia, being alert with no neurological deficit and with normal speech and limb functions.  On the next day, his condition deteriorated and he developed nominal dysphasia.  An urgent CT scan was ordered which showed white matter oedema around the evacuated haematoma involving the posterior temporal lobe.  Tests were performed which showed low serum sodium.  His condition deteriorated and, on 5 June 2006, another CT scan was performed which showed more extensive brain oedema with involvement of the left parietal lobe.  On 8 June 2006, Mr Law was transferred to Queen Elizabeth Hospital where he was under the care of Dr Samuel Leung.  Dysphasia and neglect of his right side was noted.  He was transferred to Kowloon Hospital for rehabilitation on 11 July 2006 and discharged home on 28 August 2006.  It is alleged that he currently has difficulty in comprehending simple information, and suffers from severe expressive dysphasia, and that he is also disorientated in time, place and person.  As a result, it is alleged that his ability to take care of himself is severely impaired and that he is unable to look after his own affairs. 

3.  The plaintiff brought these proceedings to claim substantial damages for personal injuries suffered as a result of the alleged negligence of the defendant.  The particulars of negligence pleaded against the defendant included  allegations of negligence during the pre-surgery diagnosis and investigation stage, as well as allegations of negligence during surgery, and during the post-surgery care and management of the plaintiff.

4.  At the checklist review hearing before Master Kwan on 13 February 2009, Master Kwan directed that the medical evidence on the issue of liability be limited to one consultant in neurosurgery for each party, and she recorded that the expert nominated by the plaintiff was Dr Samuel Leung, and the expert nominated by the defendant was Professor W.S. Poon.

5.  A case management conference was fixed to be heard before Fung J on 23 December 2009. The plaintiff’s solicitor, Mr Aaron Chow Ming Po, applied to Fung J change the plaintiff’s expert on liability from Dr Samuel Leung to Professor Christer Lindquist, Professor of Neurosurgery, who was a co-director of the Cromwell Gamma Knife Centre in Cromwell Hospital, London. As explained by Mr Chow in his affirmation of 21 December 2009, the reason for the change was that the defendant had pleaded, in §66 of the Defence, that the plaintiff’s alleged impairment and disabilities, if any, were caused by or contributed to by the poor control of his blood pressure and blood glucose levels at Queen Elizabeth Hospital and that the defendant disputed the independence of the plaintiff’s expert, Dr Samuel Leung, who managed the plaintiff at Queen Elizabeth Hospital.  The defendant did not object to the plaintiff’s application for change of expert, which was approved by Fung J at the case management conference held on 23 December 2009.  After hearing submissions from the parties, he also ordered that the parties be debarred from calling experts on liability unless the plaintiff’s new expert on liability, Professor Lindquist, held a telephone conference with the defendant’s expert on liability, Professor W.S. Poon, and they served their respective expert reports on or before 19 February 2010.

6.  The telephone conference took place on 1 February 2010 and the two experts exchanged their respective reports on 19 February 2010.  Some months passed before the defendant’s solicitors, on 8 June 2010, proposed to the plaintiff’s solicitors that they be allowed to appoint Professor Shokei Yamada, instead of Professor Poon, as the defendant’s expert on liability.  On 21 June 2010, the defendant’s solicitors took out a summons, returnable before me on 13 July 2010, for leave to instruct Professor Yamada instead of Professor Poon as the defendant’s expert on liability and for leave to serve his report within 49 days.  This summons also sought leave for the plaintiff to serve a supplemental expert report from Professor Lindquist in reply within 56 days thereafter.  The summons was not supported by any affidavit and the estimated time of the hearing given in the summons was 3 minutes. 

7.  When the matter came before me that morning, I adjourned the defendant’s summons to 15 July 2010 at 10 a.m., with 1 hour reserved, and directed the defendant’s solicitors to file and serve written submissions together with relevant correspondence and other documents in support of the application.  On 15 July 2010, the matters placed before me by the defendant’s solicitors were clearly insufficient for me to determine this application, and I further adjourned the matter and directed the defendant’s solicitors to prepare and serve a hearing bundle containing the gist of Professor Yamada’s opinions on the matter.  By the time of the adjourned hearing on 12 August 2010, I had before me a document prepared by Professor Yamada entitled a brief summary of expert opinion.  After hearing submissions from Dr Harold Leong of the defendant’s solicitors and from Ms Gekko Lan, counsel for the plaintiff, I further directed that the defendant to file and serve an affidavit setting out the circumstances resulting in the decision to change his expert on liability and I gave leave to the plaintiff to serve further submissions in response to that affidavit.  Consequent upon that direction, I received the affidavit of Dr Harold Leong sworn on 16 August 2010 and the further written submissions of Ms Gekko Lan dated 18 August 2010. 

The principles governing applications to change experts

8.  Lam J dealt with this subject in a non-personal injuries context in Chinachem Charitable Foundation Ltd v Chan Chun Chuen and Anor [2009] 5 HKC 190.  His observations apply equally to personal injury cases and bear repeating:

“20. … expert shopping is undesirable and the court should discourage such practice. When the court detects any abuse in this regard, it has the power to prevent it. In this connection, I only need to quote from para.29 of the judgment of Dyson LJ in Vasiliou v Hajigeorgiou [2005] 1 WLR 2195 at p.2205

‘The principle established in Beck v Ministry of Defence (Note) [2005] 1 WLR 2206 is important. It is an example of the way in which the court will control the conduct of litigation in general, and the giving of expert evidence in particular. Expert shopping is undesirable and, whenever possible, the court will use its powers to prevent it. It needs to be emphasized that, if a party needs the permission of the court to rely on expert witness B in place of expert witness A, the court has the power to give permission on condition that A’s report is disclosed to the other party or parties, and that such a condition will usually be imposed. In imposing such a condition, the court is not abrogating or emasculating legal professional privilege; it is merely saying that, if a party seeks the court’s permission to rely on a substitute expert, it will be required to waive privilege in the first expert’s report as a condition of being permitted to do so.’

21. Mr Yu further submitted that though the English authorities referred to the disclosure of the original expert’s report as a condition for granting permission to call a substitute expert, it is only a necessary but not a sufficient condition. I was referred to a decision by Judge Ng in Chung Tin Kau v Fong Shun Tak DCPI 1055 of 2006, 16 March 2009, where Her Honour refused permission to a plaintiff to call another doctor notwithstanding the medical report of the original expert was produced.

22. I agree that the disclosure of the original report per se may not be sufficient. The court may refuse to grant leave if the only reason for having a substitute expert is that his opinion is more favourable to the party calling him.

23. Ultimately, it is a matter of case management and one must have regard to the underlying objectives set out in Order 1A Rule 1, see Order 1A Rule 2(1). Expert shopping, if unchecked, will not be conducive to cost-effectiveness of the proceedings nor the expeditious disposal of a case. It can also lead to potential unfairness between those who can afford to shop around for the opinions of more than one expert and those who cannot. If the practice prevails, it would compromise the impartiality of expert evidence which is of great importance in the fair resolution of dispute by the court.

24. Further, the court must recognize that the primary aim in exercising the powers of the court is to secure the just resolution of disputes in accordance with the substantive rights of the parties, Order 1A Rule 2(2).

25. Hence, if the court is satisfied that the just resolution of a dispute requires leave to be granted for a substitute expert to be called, it should not refuse leave simply because the opinion of the substitute expert is more favourable than that of the original expert engaged by the same party. But I must emphasize the following: the just resolution of a dispute does not mean that whenever a party is able to obtain a more favourable opinion he should be permitted to adduce it as evidence. Such an approach flies in the face of the court’s disapproval of expert shopping.

26. In my view, the court should examine the grounds put forward by the substitute expert and make a preliminary assessment of the cogency of those grounds as compared with those set out in the report of the original expert and the report of the expert engaged by the other side. If the court is satisfied, after reading all these materials, that there are relevant matters canvassed by the substitute expert which may be important to the just resolution of the dispute that had apparently been omitted from the reports of the other experts, that would present a prima facie case for the admission of the substitute expert report in the interest of just resolution of dispute. Even so, the court must also have regard to other relevant circumstances like the potential disruption to the trial, the prejudice to the other parties, the explanation offered by the applicant for change of expert etc.

27. There can be other instances where justice demands leave to be given to a party to call a substitute expert. But I do not think it is necessary to be exhaustive for the purpose of this judgment.”

9.  The principles that have to be applied in determining an application to change an expert witness may be summarised as follows:

(a) The court’s discretion, whether or not to allow a party to change his expert, is exercised within the ambit of the court’s management powers. These powers must be exercised in the light of the underlying objectives of the recent civil justice reform, including the need to ensure the cost effectiveness of the proceedings; to ensure that the case is dealt with expeditiously; to ensure reasonable proportionality having regard to the amount of money involved, the importance of the case, the complexity of the issues, and the financial position of each party; to ensure procedural economy in the conduct of the proceedings; and to ensure fairness between the parties.

(b) In the exercise of its powers of case management, the court recognises that the primary aim is to secure the just resolution of the dispute in accordance with the substantive rights of the parties.

(c) Expert shopping is undesirable and, whenever possible, the court will use its powers to prevent it. It can lead to potential unfairness between those who can afford to shop around for the opinions of more than one expert and those who cannot. Expert shopping is not conducive to cost effectiveness of the proceedings and the expeditious disposal of a case.

(d) The disclosure of the original expert’s report, and the waiver of the privilege that would normally be attached to it, would usually be imposed as a condition for granting permission to call a substitute expert. However, the disclosure of the original expert’s report per se does not guarantee that the court would permit a substitute expert to be called.

(e) To curtail expert shopping, the court may refuse to grant leave if the only reason for calling a substitute expert is that his opinion is more favourable to the party calling him than the opinion of the original expert.

(f) However, if the court is satisfied that the just resolution of a dispute requires leave to be granted for a substitute expert to be called, it should not refuse leave simply because the opinion of the substitute expert is more favourable than that of the original expert.

(g) In every case, the court should examine the grounds put forward by the substitute expert and make a preliminary assessment of the cogency of those grounds as compared with those set out in the report of the original expert and the report of the expert engaged by the other side. If the court is satisfied that there are relevant matters canvassed by the substitute expert which may be important to the just resolution of the dispute which was omitted from the reports of the original expert, or which was outside the expertise of the original expert, a prima facie case would be made up for the admission of the substitute expert report in the interests of the just resolution of the dispute.

(h) In every case, however, the court must also have regard to other relevant circumstances, such as the potential disruption to the trial, the prejudice to the other parties, and the explanation offered by the applicant for the change of experts. All these matters have to be considered and weighed in the light of and against the underlying objectives of the civil justice reform: to ensure cost effectiveness and economy, expedition, proportionality, and fairness between the parties.

(i) It is not possible to lay down definitive and exhaustive guidelines to cover and cater for every possible situation that may arise and which prompts an application by a party to change his expert.

(j) Ultimately, the court strives to do justice between the parties and, in cases where the court permits the parties to call expert evidence, the court strives to ensure a level playing field with fair access to proper experts for all parties.

The reasons advanced by the defendant for the change of expert

10.  Dr Harold Leong for the defendant submitted that this was not an expert shopping case.  Leave was sought to adduce the expert evidence of Professor Yamada not because his evidence was more favourable to the defendant’s case.  Indeed, both Professor W.S. Poon and Professor Yamada fully and equally supported the defendant’s case.  However, the difference between Professor Poon and Professor Yamada was the quality of the evidence that he could present before the court.  Just as Professor Lindquist, for the plaintiff, was recognized as a world expert on AVM, so was Professor Yamada recognized as a world expert in the same field.  Although Professor W.S. Poon has the reputation of being one of the top neurosurgeons in Hong Kong, who has taught many, if not most, of the neurosurgeons in practice in Hong Kong today, Professor Poon’s expertise in AVM was not as extensive. Professor Yamada, on the other hand, worked at a tertiary referral centre with a much larger catchment area than Hong Kong and where he had treated patients with AVM thereby gaining substantial experience and expertise in this sub-specialization.

11.  Professor Yamada’s expertise was in surgical excision of AVM deformities.  The surgical excision by the defendant of the AVM in the present case is the subject matter of scrutiny.  One of the complaints made against the defendant was his failure to perform a digital subtraction angiography (“DSA”) to clarify the anatomy of the vascular malformation.  The defendant explained that the findings of the MRI/MRA made him conclude that he need not perform a DSA because the additional information to be expected from such a study would not justify inherent risks. Professor Lindquist had challenged the explanation of the defendant. Dr Leong submitted that the experience of Professor Yamada enabled him to adduce evidence before the court that “according to [his] studies on the complication rate of arterial angiography (including DSA) in patients with acute neurological deficit following stroke, the risk was substantial (more than 3%) and could be higher than the surgical risk for SM Grade 1 AVM”.  Professor W.S. Poon, on the other hand, did not have either the expertise or experience to present such evidence before the court, evidence which was very relevant on an important issue in the case.

12.  Dr Leong also submitted that the trial date has not been fixed yet.  The full report of Professor Yamada would be available by the time of the next case management conference in mid-September 2010.  Indeed, the report of the radiologists engaged by each party was only due to be exchanged on 9 September 2010.

13.  Given the state of the court’s diaries, I can confirm that the earliest possible trial date for this case is in the middle of next year.

14.  Pursuant to my direction, Dr Leong filed this affidavit on 16 August 2010.  In his affidavit, he explained that by the time the plaintiff applied for leave to change his expert from Dr Samuel Leung to Professor Lindquist, who was an internationally renowned expert, Professor Poon had almost finished preparing his expert report.  After discussion with the Defendant, Dr Leong, and Professor Poon, who knew Professor Lindquist, it was decided that there would be no need for the defendant to change his expert to an internationally renowned expert if there was no substantial dispute in the parties’ expert opinions.  They, therefore, welcomed the direction of Fung J that a telephone conference be held by the experts before the service of their reports.  That telephone conference took place on 1 February 2010.  From their discussions with Professor Poon after the telephone conference, the defendant and Dr Leung understood that there was much agreement between him and Professor Lindquist and that any difference of opinion that remained concerned matters which were not causative of the alleged damage in the present case.  Professor Poon then prepared his report dated 18 February 2010, setting out the issues agreed between him and Professor Lindquist, including their agreement that the surgical option was a reasonable option in the present case, that this was a case of arterial infarct of the left middle cerebral artery (“MCA”) after the operation, which, it was agreed, was a rare complication and unpredictable complication following AVM excision surgery, and that the post-operative management of the plaintiff’s complications was reasonable.  Although they disagreed on the timing of the surgery and the need for a DSA, Professor Poon was of the opinion that the timing of surgery was not related to the occurrence of left MCA infarction and further, that, in his opinion, the occurrence of the rare complication of left MCA infarction was not related to whether or not the DSA was performed. 

15.  When the expert reports were exchanged, the defendant and Dr Leong were concerned that the report of Professor Lindquist only devoted two paragraphs to the discussions between him and Professor Poon.  Further, Professor Lindquist did not mention any of the agreements on issues that Professor Poon thought they had discussed and reached.  In particular, Professor Lindquist stated that the present case was likely to be a venous infarction when Professor Poon thought that there was an agreement between them that the present case was a case of an arterial infarction.  

16.  Having realized that substantial disputes and differences of opinion existed in the present case between Professor Poon and Professor Lindquist, they started to take steps to engage Professor Yamada, the internationally recognized expert on AVM, to prepare a report in this case, and those steps led to the application being made on 21 June 2010 for Professor Yamada to be called in place of Professor Poon as the defendant’s expert. 

The plaintiff’s opposition to the present case

17.  Clearly, Ms Gekko Lan for the plaintiff is right to submit that the defendant went about their application the wrong way by not filing an affidavit in support of the application until nearly two months later and then only upon the direction of the court to do so.  However, a wrong footed application is not a ground to dismiss it if, ultimately, the applicant manages to get his house in order. Costs ought to be paid for the wrongful steps taken that resulted in costs being raised or thrown away.  I, therefore, turn to consider the substantive grounds of opposition raised by Ms Lan.

18.  Ms Lan submitted that if the different reasons advanced by the defendant at different stages for the change of expert were properly analysed, that analysis would demonstrate that this was a classic case of expert shopping.  In my view, except in cases where an expert is incapacitated by reason of death or disability from giving evidence, it is more likely than not that a party seeking to change an expert will seek to adduce evidence from the new expert which is more favourable than the evidence adduced by his previous expert.  All these cases can be said to be cases of expert shopping.  It is for that reason that the court is unlikely to grant leave to change an expert if the only explanation advanced for the change is that he can give more favourable evidence than the previous expert.

19.  One must not lose sight of the fact that the purpose of expert evidence is to assist the court on areas of specialist knowledge and expertise that is outside the scope of common knowledge and experience.  As a general statement, it can be said that the court is likely to obtain greater assistance from the specialist than from a generalist.  When an application is made to change a expert on the ground that the new expert has greater knowledge and experience in a particular area, the issue takes on a different dimension and the question the court has to ask is whether his greater expertise and knowledge is required by the court to resolve any particular issue or issues that have arisen.  The question then is not just whether or not the opinion of the specialist is more favourable but whether his greater expertise is required to assist the court to determine the case.  The answer to that question depends on the issues raised: are they central or peripheral to the determination of the case; and, if peripheral, the greater assistance the specialist may provide to the court on the issue(s) must be balanced against other considerations such as proportionality, added costs and expenses, disruption to trial dates.

20.  Ms Lan also submitted that the reason initially advanced for the change of expert, namely, that “it was only as the case unfolded over the last few years through repeated examination of the case and radiological investigations that the defendant realised the full extent of the complexity of the issues involved” was inconsistent with and contradicted by the explanation advanced in Doctor Leong’s affidavit that they did not consider that a change to an internationally renowned expert was warranted, when Doctor Samuel Leung was replaced by Professor Lindquist, because, if there was “ no substantial dispute in the parties’ expert opinion, there would be no need to change our expert to an international one” and that, as it later transpired that “substantial dispute still existed…, it was at this stage that [they] started considering an experienced vascular neurosurgeon to address, in particular, the practice of AVM surgeries at an international level”.  I accept these submissions.  Clearly, the initial reason advanced was without substance and not a valid reason as would persuade the court to allow a change of expert.  The complexities of the case and of the issues involved were known to the defendant and his legal advisers from the outset.  It is incumbent on the parties seeking the court’s indulgence to be frank and upfront from the start.  The way the defendant has gone about making this application leaves much to be desired.  The lack of frankness from the outset, and the reliance on unsustainable reasons, must weigh on the exercise of the court’s discretion whether or not to grant leave to change experts.

21.  Ms Lan also complained about the delay in making the application. Although Professor Lindquist’s report was served on 19 February 2010, it took the defendant and the Medical Protection Society three months to confirm that steps would be taken to change to change experts and another three weeks passed before the plaintiff solicitors received notice of the intended application.  Ms Lan submitted that this delay ought to prompt the court to look at the conduct of the defendant more closely.  At the first hearing on 13 July 2010, the defendant was utterly unprepared, appearing without an affidavit in support and no draft report from Professor Yamada.  At the adjourned hearing on 15 July 2010, there was no draft report and the solicitor appearing for the defendant offered little assistance except to inform the court that the handling solicitor, Dr Leong, was on leave.  On that occasion the court granted a further indulgence by adjourning the application to 11 August 2010 (the hearing in fact took place on 12 August 2010) to enable the defendant to serve a summary of Professor Yamada’s opinion.  At the hearing on 12 August 2010, the court granted a further indulgence by allowing Dr Leong to file an affidavit in support of the application. Ms Lan submitted that no further indulgence should be granted and that the present application should be dismissed.

Discussion

22.  A late application to change experts which would impact on a milestone date and result in trial dates being adjourned is unlikely to be acceded to without very good and compelling reasons, such as incapacity from death or disability preventing the current expert from giving evidence at trial.  The present case is not such a case.  Trial dates have not had been fixed and the earliest available date for trial appears to be in the middle of next year.

23.  When one party obtains leave from the court to change his expert from a local expert to an internationally renowned expert, the other party, if he feels disadvantaged by the leave granted, should apply at the same time or soon thereafter for leave to change his own expert from a local to an internationally renowned expert.  To ensure a level playing field, a court which allows one party to make the change experts is likely to allow the other one to do so as well.  In this case, the defendant considered applying for a change of expert but decided to continue to engage Professor Poon in the hope that he and Professor Lindquist could reach agreement on the medical issues.  Having made this decision, the court would be slow to allow a party to change his mind at a later time without good reason.  The seeming unfairness of allowing one party to call an expert of international repute and preventing the other party from doing so as well is more than ameliorated by the latter’s decision to continue to engage his local expert.

24.  In my judgment, it is not a sufficient or good reason for a party to assert, in order to justify his later change of mind, that the agreement on issues, which he anticipated that the other side’s new expert would reach with his own expert, did not materialise.

25.  However, in my judgment, a valid ground for the change of expert is provided by the present state of affairs in connection with the expert medical evidence on liability.  Professor Poon believes, as a result of his telephone conference with Professor Lindquist that there is agreement between them on all relevant causative issues and that the disagreement between them only pertains to non-causative aspects of the defendant’s treatment and management of the plaintiff.  There is no reflection of any such agreement in the report prepared by Professor Lindquist.  Instead of reducing controversy, the dealings between the experts have created further controversy as may require the trial judge to decide whether any agreement was reached as a result of the discussions between the experts and, if so, what agreement.  Ideally, a direction should be given for there to be a “without prejudice” meeting or conference of the parties’ respective experts, without the presence of legal representatives, for the purpose of identifying those parts of their evidence in relation to liability and causation on which they are in agreement and those parts of their evidence on which they disagree, and for the experts to record the same in a document jointly produced by them, whether or not they also prepare a joint report or separate reports.  In this way, controversy is avoided and, hopefully, issues are narrowed.  To permit the defendant to call Professor Yamada as his expert, instead of Professor Poon, would enable this course to be taken.  Doing so would avoid the disagreeable spectacle of two renowned experts making accusations and cross accusations against each other.

26.  Having considered and weighed all the relevant factors, including those set out above, that cause me to exercise my discretion against granting leave to the defendant to change experts, and balancing them against the matters canvassed in the preceding paragraph, the specific expertise of Professor Yamada on the risks associated with DSA, the fact that the trial dates would not be affected by the change, that the claim is for substantial damages, and that these proceedings impact on the reputation of a professional person, I have come firmly to the view that I ought to allow the defendant to call Professor Yamada as his expert instead of Professor Poon.  I will give further directions in that connection at the next case management conference.

27.  The defendant must pay the costs of the application to the plaintiff, including the costs of the hearings on 13 July, 15 July and 12 August 2010.  Whilst I do not order costs to be paid on an indemnity basis, I will be generous in my summary assessment of the costs payable to the plaintiff.  The costs of the first two hearings were largely wasted because the application had not been properly brought, and had not been properly supported by an affidavit setting out the circumstances which prompted the application, and the grounds of the application, and exhibiting the opinion or, at least, the gist of the opinion of the new expert.  I direct the plaintiff to file a skeleton bill of costs within 14 days and the defendant to respond to it 14 days thereafter.

28.  A party should not take out a 3 minutes’ summons before the Personal Injury Judge for leave to change experts, unsupported by affidavit evidence, as the defendant has done here, on the pretext, which I do not accept, that the summons was a case management summons and Order 25, rule 6 RHC applied to prevent the parties from filing affidavit evidence in support thereof.  Whether or not an application for change of experts is made at a case management conference, or at a pre-trial review, or by a separate summons, the application should be supported by an affidavit setting out the circumstances which prompted the application, and the grounds of the application, and exhibiting the opinion or, at least, the gist of the opinion of the new expert.  Where milestone dates are threatened and the application has to be made urgently, the court may be prepared to accept written submissions instead of an affidavit but the court cannot properly exercise its discretion in the matter without sight of the opinion of the new expert.