Getting experts’ joint statements right


In the judgment of Master Cook in the case of Aderounmu v Colvin [2021] EWHC 2293 is another example of what can go wrong with the joint statements of experts following a joint discussion.

  1. [The psychiatrists] produced a joint statement dated 22 December 2020. Unfortunately, this is an overly-lawyered document comprising 34 questions many of which had numerous sub-clauses and in places descended into cross-examination. This is not helpful to the court. A joint statement should aid the understanding of key issues and each expert’s position on those issues.
  1. The [neuro-psychologists’] joint statement dated 14 January 2021 suffered from the same vice as that of the psychiatrists; it is an overlong overly-lawyered document which asked many questions which were nothing more than a cross-examination of the experts on their respective approaches, or attempts to advance the arguments on behalf the parties’ respective positions. Of the 41 questions posed only about 2 were of assistance to me in understanding the issues on which the experts agreed, the issues on which they disagreed and the reasons for their disagreement.
  2. Parties should resist the approach that has been taken in this case.  A joint statement by experts pursuant to CPR 35.12 is for the benefit of the court and should not be a proving ground for the parties’ respective cases. Written questions should be put to experts under CPR 35.6 within 28 days of the service of an expert’s report.

A similar problem arose in the earlier case of Saunders v Central Manchester University Hospitals NHS Foundation Trust [2018] EWHC 343 where the judge said:

34. Both experts provided clear reports that were easy to read; thorough and attractively presented with useful diagrams attached. However, their joint statement was disappointing. It was 60 pages long and did not fulfil the purpose identified in CPR 35PD 9.2 “to agree and narrow issues”. It seemed to me that the difficulty may have arisen not through the fault of the experts but through the way in which the agendas were drafted. I say “agendas” because, for reasons not explained to me, there had apparently been two separate agendas that the experts were required to consider. Both involved repetitive questions for the experts and far from producing a focus on the real issues, the result was a document that served only to confuse rather than assist.

35. I can see no good reason why the parties were unable to agree a single agenda in this case. Perhaps greater input from Counsel may have assisted. …Frankly, the approach to the joint statement in this case achieved nothing of value.

There is, in these cases, criticism of the lawyers involved, but it is the experts who are responsible for producing, and signing off on, a joint statement.  The experts must therefore understand what it is they are supposed to be doing and take responsibility for it, and if necessary take action to remedy any difficulties that arise.

The procedural framework

Let’s go back to what the purpose of the joint discussion is supposed to be.  The Practice Direction to Part 35 of the Civil Procedure Rules is quite clear and provides:

9.2 The purpose of discussions between experts is not for experts to settle cases but to agree and narrow issues and in particular to identify:

(i) the extent of the agreement between them;

(ii) the points of and short reasons for any disagreement;

(iii) action, if any, which may be taken to resolve any outstanding points of disagreement; and

(iv) any further material issues not raised and the extent to which these issues are agreed.

The purpose of doing this is to assist the court at the trial, and the parties both at the trial and in the lead up to it, in understanding precisely what expert issues remain to be determined, and where each expert stands on those issues on which they do not agree.

Therefore, left to their own devices the experts should, in the course of the joint discussion, ascertain, and set out in the joint statement, their points of agreement, the points of disagreement and the reasons for such disagreement, and whether anything could be done to resolve the remaining areas of disagreement between them.  This should be relatively brief.  Both experts have already produced written reports in which they should have explained their positions in some detail, so that the joint statement should only need to set out the positions briefly. 

To make matters as clear as possible to the lawyers, it is necessary to separate the points of agreement from the points of disagreements – it is surprising how many joint statements fail to do this – numbering each point, and, in relation to the points of disagreement, summarising in relation to each one the basis for the disagreement.  In doing this, what is written must be easily understood by a lawyer, and in terms of the audience’s medical expertise it may be useful to imagine that the experts are addressing year 1 medical students.  In this way, the minds of all involved in the litigation can be focussed on the reasons why the experts have been unable to agree, which will form the principal area of investigation (and cross-examination) at the trial.

The Practice Direction contains this further important statement:

9.7 Experts must give their own opinions to assist the court and do not require the authority of the parties to sign a joint statement.

And related to this the Guidance for the Instruction of Experts in Civil Claims (the Guidance) provides:

77 Lawyers must not instruct experts to avoid reaching agreement on any matter within the experts’ competence.

The joint statement is the experts’ document, and not the lawyers’.

To reinforce these points, the joint statement is required, by para 80 of the Guidance, to include:

1. A brief re-statement that experts recognise their duties AND

2. An express statement that the experts have not been instructed to avoid reaching agreement on any matter within their competence.


In Aderounmu v Colvin and Saunders it was the lawyers who contributed to creating the ‘over-lawyerly’, unhelpful and overlong joint statement.  Lawyers do have a role in relation to producing an agenda. The Practice Direction provides:

9.3 Where the experts are to meet, the parties must discuss and, if possible, agree whether an agenda is necessary, and if so attempt to agree one that helps the experts to focus on the issues which need to be discussed. The agenda must not be in the form of leading questions or hostile in tone [my emphasis]

It seems likely that the agenda(s) provided to the experts in these cases did not help the experts focus on the issues needing to be discussed – identifying the areas of agreement, disagreement and the reasons for disagreement – and that they were in the form of cross-examination, and therefore quite probably contained leading questions hostile in tone.  It is not the purpose of the joint discussion to deal with such questioning and it is not the role of the joint statement to record answers to such questions, although there may be some scope for this separate from the joint discussion in Questions to experts on their reports under CPR 35.6.

The Guidance provides in relation to the drafting of an agenda:

75 Primary responsibility for preparation of the agenda should normally lie with the parties’ solicitors

76 The agenda should indicate what has been agreed and summarise concisely matters that are in dispute

An agenda may be used quite properly by lawyers to ensure that the experts address the issues which require to be addressed for the purpose of the litigation, and to ensure that any legal tests relevant to that are properly considered and applied.  That is an important role for the agenda.  For example, if the experts have failed properly to address the standard of proof or the Bolam test or rules of causation in relation to damages then the agenda should seek to get them to do so.

If the expert is uncomfortable because of the length of an agenda or the nature of its questioning or the hostility it demonstrates, then they should raise their concerns with their instructing solicitor, referring if they wish to the Practice Direction and the Guidance.  If the solicitor fails to address this adequately, whether the agenda is one produced by them or the other side or both sides, then the expert can resort to seeking directions from the court as to whether the questions should be answered, under CPR 35.14. (For more on seeking directions from the Court, see Section 4.6.2 in Writing Medico-Legal Reports in Civil Claims – an Essential Guide – Eyre and Alexander.)

While the experts must ensure that the joint statement deals with the matters set out in 35PD 9.2 (above), they should also (and if they consider it appropriate, separately within the joint statement) answer the questions in the agenda(s) unless an order is obtained from the Court releasing them from having to do so.

Learning points

The joint statement is an important document. It ought to be possible to read it and to understand the key issues and each expert’s position on those issues. Sometimes less is more as far as the agenda is concerned.

Parties should adopt a common sense and collaborative approach rather than allowing this stage of the litigation to become a battleground. (Yip J in Saunders v Central Manchester University Hospitals above)

Many difficulties with the joint statement can be avoided if the expert follows this guidance:

1. Prepare for the meeting, by:

  1. Identifying the issues between the experts – both legal and expert
  2. Analysing the evidence which relates to the expert issues
  3. Preparing a process for the meeting to ensure that the functions of a joint discussion are properly and fully addressed – areas of agreement, areas of disagreement and reasons for disagreement.

2. Remember that the precise wording of the joint statement is crucial.  The audience is made up of lawyers, to whom words matter, and the expert is working in the legal arena and therefore needs to apply the appropriate legal tests accurately.

3. Produce in the joint statement a document that a non-medically qualified person can read in order to understand the key issues and each expert’s position on those issues.

[Who or what is medico-legal minder?  Terms and conditions apply]

The Inconsistency of Experts and the Failure to Apply the Legal Tests

In a recent High Court case[1] concerning allegations of clinical negligence in relation to a hip replacement surgery, the judge concluded that the Defendant’s expert was ‘lacking credibility and understanding as to the applicability of the legal test’, and found the expert was not ‘an impressive witness’.  We must accept of course that often, once a judge decides to prefer the evidence of one expert over another, the justification may be in harsh terms.  But it is educative to consider what caused the judge to form this view in this particular case.

The case concerned a total hip replacement that failed and was identified as having failed the day after surgery when on x-ray dislocation was confirmed.  The agreed position of the experts in the joint statement  was that ‘we both agree that on the balance of probabilities the cause [of the post-operative dislocation] was a loose acetabular component’ and that ‘on the balance of probabilities an acceptable and competent press fit [of the acetabular component] was not secured intraoperatively’.  This agreement might have been thought to have resolved the issue on breach of duty;  if the operating surgeon had not achieved an ‘acceptable and competent’ degree of security to the component that might be thought to have been equivalent to a statement by both experts that the degree of security achieved fell below that reasonably to be expected of a reasonably competent surgeon in that field (the Bolam test).  Indeed that is how the Claimant’s counsel opened the case.  However it transpired that the Defendant’s expert did not mean to criticise the performance of the surgery, but merely intended thereby to describe the result, without comment on the standard of care demonstrated.

Answering the right question

The first lesson from this case is the importance of posing the right questions for liability experts to address in a joint statement and the importance of liability experts providing answers which address the relevant legal test.  Drafting the questions in the agenda for a joint discussion is the primary responsibility of the lawyers but the competent medico-legal expert must be aware of the legal tests which his or her evidence is to address, and in a clinical negligence claim that will (almost always) include addressing the Bolam test of negligence.  The question posed here was arguably ambiguous – ‘Was an acceptable and competent pressfit secured?’ Did that refer to performance by the surgeon or merely outcome?  Nowhere in the Bolam test does the word ‘acceptable’ or ‘competent’ appear.

Changing opinion

The second lesson is that the expert who changes his or her opinion is at risk of being found an unreliable expert – and that risk is greater the later the change occurs.  A change of opinion certainly needs rational justification.  In this case the change came in response to formal questions put to an expert by his own side after the joint statement and after a conference with counsel, and in the days before trial.  (These could not have been questions under CPR 35.6 which relates only to questions put to another party’s expert and imposes time limits on the asking of questions.)  In this case this process appears to have been used to put into the open answers which the expert had been prepared to give in conference to his own team on further discussion of, and clarification of, the joint statement and its implications.

In these answers the expert resiled from the previously agreed position that it was more likely than not that a loose acetabular cup had caused the subsequent dislocation, making this now only ‘a possibility’, moving, it appears, from a 51% likelihood to a 50:50 possibility.  He put forward 3 other explanations (soft tissue impingement, a haematoma and abnormal movement of the leg), regarding each of the explanations as equally possible.  The expert’s further suggestion that it was ‘very possible’ that a reasonable press fit had been obtained at surgery but that it was only loosened on dislocation of the hip the following day ‘as stated in my [earlier] report’ was not something that the judge was able readily to identify in that earlier report.

The judge noted that ‘the court should be slow to criticise an expert who does change an opinion, and prefers a frank expression of view rather than an unswerving adherence to an original position’.  But the judge found that the expert’s reasoning for his new position ‘disjointed’ and that he was ‘endeavouring to add plausibility to what were essentially very remote possibilities’ and that he had ‘strained to identify possibilities which in most respects are so remote as to be fanciful.’  Most damning, the judge concluded that the expert ‘lacked credibility and understanding as to the applicability of the legal test by resiling so dramatically and so recently from a position jointly adopted’,  while accepting that that these opinions were held ‘genuinely and honestly’.


The expert, as well as the instructing lawyer, must be aware of the legal test(s) applicable to the matters on which opinion is being sought and the expert must give opinion by reference to those legal tests, for example the balance of probabilities and the Bolam test.  And while it is only right that, in accordance with the expert’s duty to the court, any change of opinion in the course of the expert’s involvement should be communicated at the earliest opportunity, the time for careful consideration of the case, its facts, alternative explanations, the reasoning process and the opinion itself is when preparing a written report.  While an ‘unswerving adherence’ to an opinion no longer confidently held must be avoided, any subsequent changed opinion will need to be justified in a similar and convincing manner if the expert expects the changed opinion to carry weight in court.

[1] Pullen v Basildon & Thurrock University Hospitals NHS Foundation Trust [2015] EWHC 3134