In Pickett v Balkind [2022] EWHC 2226 (TCC) HHJ Paul Matthews (sitting as a High Court Judge) refused the claimant’s application for an injunction to prevent the defendant relying on the contents of a letter from the claimant’s expert. That letter indicated that the claimant’s legal team had some input into the preparation of the expert’s report following the joint meeting of experts.

“..the first four paragraphs appear to reveal a breach of the expert independence principle. To my mind those paragraphs are less worthy of protection than the remainder, but the remainder is the part which most justifies the reference to the letter in the witness statement of the solicitor. Accordingly, I conclude that privilege has been waived in the whole of the letter of 3 May 2022, and (as I have already said) no injunction should be granted to restrain use of the information contained in it.”


The claimant brings an action alleging that the defendant’s tree roots are damaging her property. Both sides have permission to call two experts.  The claimant instructed an expert structural engineering report.  There was an order that the experts meet and provide joint reports.


The matter was listed for trial, however one of the claimant’s experts, was due to be undergoing surgery on the trial date.  The claimant therefore applied for an adjournment. It attached to the  draft adjournment application the full text of a letter from the expert.  That letter made it quite clear that the claimant’s legal team had had some considerable involvement in the drafting of the joint report of the expert.


    1. On 9 May 2022 the claimant’s solicitors informed the defendant’s solicitors that Mr Cutting would not be available to give evidence at the trial as listed, as he would be undergoing surgery on 13 July 2022. Accordingly, the defendant was asked to consent to an adjournment of the trial. The defendant asked to see a draft application for this purpose. On 26 May 2022 the claimant’s solicitors sent the defendant’s solicitors a draft application for an adjournment, supported by a draft (unsigned) witness statement from the claimant’s solicitor, Christian Charlesworth. This draft witness statement referred in its body to a letter to the solicitors from Mr Cutting dated 3 May 2022, a copy of which was intended to be exhibited to the statement when made. An unredacted copy of this letter was sent with the draft witness statement. The text of the draft witness statement in part read as follows:
“11. On 3 May 2022 Mr Cutting wrote to me to say that he has been advised by his doctor that he will need to undergo eye surgery and has been given the date of 13 June 2022 for this procedure to be carried out. He added that due to the recovery period, he would not be able to attend the court to give evidence over the current trial dates, 12 15 July 2022., Attached hereto marked Exhibit [CC2] is a copy of Mr Cutting’s letter.”
Mr Cutting’s letter
    1. The substance of the letter as sent is as follows:
I have been through Daniel’s comments on the Joint Statement and have made just a couple of minor changes where I was unable to be as definite as his wording.
Attached is a word doc for your/Daniel’s comment.
The only area where I have not dealt the suggestions/requests from Daniel is Clause 1.7, Daniel asked how desiccated, looking I assume for a figure. The desiccation of clay is open to substantially different interpretations. There is no clear level of desiccation shown by the testing and further this testing was carried out in March when you would expect desiccation to be the lower. I am not happy to put a figure in here. There may be some desiccation at 1.6 to 1.8 metres below ground level, possibly 2 or 3 %. However, if we start down this course of discussion, the Defendant might argue that taking the tree down would cause this zone to rehydrate and in turn create heave damage on the property, hence be better to keep the tree. That is not a particularly sound argument because there is not a large amount of desiccation, but it would however open up a whole new area of discussion where definite answers are difficult if not impossible to come by.
Please note that I have given a completely new and separate proof for T13 in para 1.10. I hope you agree that this explains the lack of roots from any tree bar T13 thus dismissing many of the arguments from the defendant including those from Martin Dobson Ass. I will expand this methodology in my report, [comma in original]
I am afraid I will not be able to attend Court in July. I was unavailable at the end of last week as I was seen by an eye consultant. I need an operation to hopefully restore full vision to my left eye. This is booked for the 13th June. I would hope to complete my report for you before that date. However, after the operation I will not be able to drive for probably 6 weeks and will not be able to read properly for in excess of 4 weeks. Further, I will have to take precautions to avoid infection after the operation.
I have discussed my Opinion with one of my colleagues here at length and he is of the same view as I. He could attend Court with you if that would help.”
I should add that it was confirmed to me at the hearing that the references to “Daniel” were references to Mr Daniel Crowley, counsel for the claimant.


The defendant was concerned about the contents of the letter.  It was wrong, the defendant argued, for the legal team to have this level of involvement in the preparation of the joint report.
    1. On 7 June 2022 the defendant’s solicitor Charles Brine wrote by email to the claimant’s solicitors as follows:
“We are concerned with comments made by Mr Cutting in his letter to you of 3 May 2022. Mr Cutting states:

I have been through Daniel’s comments on the Joint Statement and have made just a couple of minor changes where I was unable to be as definite as his wording

I refer you to the TCC Guidance at 13.6.3:

‘13.6.3 Whilst the parties’ legal advisors may assist in identifying issues which the statement should address, those legal advisors must not be involved in either negotiating or drafting the experts’ joint statement. Legal advisors should only invite the experts to consider amending any draft joint statement in exceptional circumstances where there are serious concerns that the court may misunderstand or be misled by the terms of that joint statement. Any such concerns should be raised with all experts involved in the joint statement.’

We are concerned that your client has breached the guidance at paragraph 13.6.3 in that it appears a Daniel (Mr Crowley?) was involved in drafting the experts’ joint statement. I refer you to BDW Trading Limited v Integral Geotechnique (Wales) Ltd [2018] EWHC 1915 (TCC). Please may I have an explanation as to the interventions made on behalf of your client and how this may have affected the joint statement.
Please will you also confirm whether your client was involved in drafting amendments to the joint report of the arborists.
In respect of your expert engineer’s availability for trial, your application indicates Mr Cutting shall be available from 11 July (4 weeks from 13 June) but that a further 2 weeks is required for an eye test and glasses to be obtained. We are concerned that the comment on the further 2 weeks does not come from a medical source but appears to be a colleague of Mr Cutting. Is there any medical opinion to support Mr Cutting not being available for 2 weeks? Can the court not accommodate an expert who has poor visibility?”
    1. I assume that the reference in that email to BDW Trading Limited v Integral Geotechnique (Wales) Ltd [2018] EWHC 1915 (TCC) is a reference to para 18 of the judgment, where HHJ Stephen Davies says:
“What happened here was, I agree, a serious transgression and it is important that all experts and all legal advisers should understand what is and what is not permissible as regards the preparation of joint statements. To be clear, it appears to me that the TCC Guide envisages that an expert may if necessary provide a copy of the draft joint statement to the solicitors, otherwise it would not be possible for them to intervene in the exceptional circumstances identified. However, the expert should not ask the solicitors for their general comments or suggestions on the content of the draft joint statement and the solicitors should not make any comments or suggestions save to both experts in the very limited circumstances identified in the TCC Guide. That is consistent with the fact that any agreement between experts does not bind the parties unless they expressly agree to be so bound (see Part 35.12(5)). There may be cases, which should be exceptional, where a party or its legal representatives are concerned, having seen the statement, that the experts’ views as stated in the joint statement may have been infected by some material misunderstanding of law or fact. If so, then there is no reason in my view why that should not be drawn to the attention of the experts so that they may have the opportunity to consider the point before trial. That however will be done in the open so that everyone, including the trial judge if the case proceeds to trial, can see what has happened and, if appropriate, firmly discourage any attempt by a party dissatisfied with the content of the joint statement to seek to re-open the discussion by this means.”


The claimant then sought an injunction to prevent the defendant from using the witness statement and letter sent in support of the draft application.


The defendant responded with a number of applications.
    1. On 8 July 2022, the defendant issued the expected cross-application. However, it sought two quite different orders. First of all, it sought an order under CPR rule 35.10(4), based on Mr Cutting’s letter, asking for (1) the production
“for inspection by the Defendant a copy of the written instructions/comments/aide memoire provided to Mr Cutting by [the claimant’s solicitors] for the purpose of the preparation of the Joint Statement of the engineers dated 18 May 2022”,
(2) permission
“to cross-examine the Claimant’s experts at trial as to the preparation of their joint statements and the completeness of their statements of their instructions”,
and (3) permission
“to deploy in evidence at trial the letter from Mr Cutting to [the claimant’s solicitors] dated 3 May 2022”.
    1. Secondly, the defendant sought an order under CPR rule 31.14(2) that the claimant should
“produce for inspection by the Defendant a copy of the Prior Associates report referred to by Mr Pryce in paragraph 3.9(2) of the joint statement of the arboriculturalists dated 19 May 2022 and paragraph 9.6 of his report dated 12 June 2022.”
In fact, I think the paragraph numbers have become reversed, and it should read “paragraph 9.6 of the joint statement of the arboriculturalists dated 19 May 2022 and paragraph 3.9(2) of his report dated 12 June 2022.” But no point is taken on that. The witness statement of Mr Brine, the defendant’s solicitor, dated 8 July 2022 and referred to above, was also made in support of this application.


The judge dismissed the claimant’s application for an injunction.
    1. In considering this case, I begin with the question whether the letter from Mr Cutting to the claimant’s solicitor was privileged. Mr Crowley says it was. The test for a privileged communication such as this is whether it is confidential and made between a lawyer and a third party for the sole or dominant purpose of the existing litigation: Three Rivers District Council v Bank of England (No 6) [2005] 1 AC 610, [102]. Here there was no reason for Mr Cutting to write to the solicitor but for the litigation, and some of what he wrote had the necessary quality of confidence. However, in the first four substantive paragraphs of his letter, Mr Cutting reveals that he has received comments and suggestions for his evidence from the claimant’s lawyers. This is potentially a serious breach of para 13.6.3 of the TCC Guidance, quoted above. I have seen nothing to show that there are “exceptional circumstances where there are serious concerns that the court may misunderstand or be misled by the terms of that joint statement.” I accept that the remainder of the letter is prima facie confidential (though paradoxically it is the very part in which privilege would be likely to be waived).
    1. Accordingly, on the whole I am doubtful the first four paragraphs of Mr Cutting’s letter could qualify as a privileged communication. If however they were privileged, the question is whether that privilege survives the sending of the letter in unredacted form to the other side. Clarke LJ refers to this as the question whether privilege has been waived, and that is the process involved. But it is intimately tied up with whether an injunction will be granted to restrain its use. If it will, then – as a general proposition – privilege is not waived. If it will not, then privilege has usually been waived.
    1. There is no doubt that the letter was intended to be sent, in order to support the statement in the solicitor’s witness statement that Mr Cutting would be unable to attend the trial in July to give evidence. It need not have been sent, but it was. There is no doubt that it provided powerful support for the witness statement. Ms Chalmers, for the defendant, says that this act waived any privilege there might be, in the whole letter. Mr Crowley, for the claimant, says that it did not. He accepts that privilege was waived (as it was intended to be waived) in the final two paragraphs, but not the remainder.
  1. I have already held that (i) Mr Charlesworth made an error in sending the letter unredacted, but (ii) Mr Brine did not realise the error, and (iii) neither was it obvious. It is also the case that the first four paragraphs revealed a potentially serious breach of the TCC Guide, which the defendant raised immediately with the claimant, but to which there was no satisfactory response. It would promote a sense of injustice in the defendant to leave that concern hanging, unanswered. Even without that reliance by the defendant on the letter to raise his concerns, I do not consider that it would be right to grant an injunction restraining the use of the information in the letter (including the first four paragraphs). But that concern and reliance, and the risk of the sense of injustice, go to strengthen my conclusion.
    1. In the present case, the claimant has exhibited a letter from his expert in order to seek an adjournment of the trial. The claimant has not (as he could have done) merely referred to the letter, but has deployed its contents. I accept that this does not go to the merits of the whole case, but instead merely to the merits of the adjournment. Mr Charlesworth says that the first four paragraphs do not go to the merits of the adjournment. I do not think that, even if true, this in itself matters. The whole letter is deployed. It need not have been, but it was. It therefore raises the question already posed by earlier judges, in particular Waller LJ in Dunlop Slazenger and Gloster J in Berezovsky, as to whether it matters that the issue to which the disclosed privileged material goes is relevant only to interlocutory matters, or goes to the merits of issues at trial.
    1. For my part, I do not think that Vinelott J distinguished between the two cases. Instead, he distinguished between the effect and the contents of what was disclosed. But it is also correct that, in his case, the disclosure in fact went to the merits of the whole case. Looking at the matter on principle, it is not easy to see why a waiver of privilege only for the purpose of interlocutory proceedings and in relation to an issue in those proceedings should mean that the waiver “was in some way limited”. After all, the principle is one and indivisible: once privileged, always privileged, as Sir Nathanial Lindley MR put it in Calcraft v Guest [1898] 1 QB 759, 761, though of course, as he then said, that does not “mean to say that privilege cannot be waived”; and see also the recent decision of the Court of Appeal in Addlesee v Dentons Europe LLP [2020] Ch 243.
    1. I accept that privileged information can be shared with some others, on a confidential basis, without yet waiving the privilege: see eg British Coal Corporation v Dennis Rye Ltd (No 2) [1988] 1 WLR 1113, CA (disclosing to the police for the purposes of a criminal investigation). Nevertheless, only information that is confidential as against the opponent can be privileged, and by disclosing the confidential information to that opponent, it thereby loses the quality of confidence necessary to engage the doctrine of privilege in the first place. I regret that I am unable to agree with the decision of Birss J. In my judgment, if there is a deliberate disclosure of information by a party to its opponent, even for an interlocutory purpose, it ceases to be confidential as against that party, and hence loses its privilege.
    1. Moreover, I see no justification for separating out, and treating differently, the different parts of the letter in this case. As I pointed out earlier, the first four paragraphs appear to reveal a breach of the expert independence principle. To my mind those paragraphs are less worthy of protection than the remainder, but the remainder is the part which most justifies the reference to the letter in the witness statement of the solicitor. Accordingly, I conclude that privilege has been waived in the whole of the letter of 3 May 2022, and (as I have already said) no injunction should be granted to restrain use of the information contained in it.
    1. I accept that this means that the tentative suggestion in the first sentence of paragraph 16.24 of Matthews and Malek is at least misleading, if not simply wrong. But legal authors and judges have completely different functions, as Megarry J pointed out in Cordell v Second Clanfield Properties Ltd [1969] 2 Ch 9, 16-17:
“The process of authorship is entirely different from that of judicial decision. The author, no doubt, has the benefit of a broad and comprehensive survey of his chosen subject as a whole, together with a lengthy period of gestation, and intermittent opportunities for reconsideration. But he is exposed to the peril of yielding to preconceptions, and he lacks the advantage of that impact and sharpening of focus which the detailed facts of a particular case bring to the judge. Above all, he has to form his ideas without the aid of the purifying ordeal of skilled argument on the specific facts of a contested case.”
And Megarry J himself, legal polymath that he was, was not the first legal author turned judge to find that he had authored something that he later could not agree with in his judicial capacity: compare Tito v Waddell [1977] Ch 106, 248G. I am sure I will not be the last.


The judge considered the defendant’s cross-application for disclosure of documents sent to the expert. He declined to order disclosure, but did order that the expert could be cross-examined about these documents.
    1. I now turn to consider the defendant’s cross-application for (1) production for inspection of “the written instructions/comments/aide memoire” provided to Mr Cutting, (2) permission to cross-examine the claimant’s experts at trial, and (3) permission to deploy the letter from Mr Cutting in evidence at trial. As to point (3), this is the other side of the claimant’s application for an injunction. Since the application has failed, there is no reason not to give permission to deploy the letter in evidence. I am not sure that it is actually necessary to give permission, but for the avoidance of any doubt I will do so.
    1. The other two points in this application are more substantial. They depend on CPR rule 35.10(4), which I set out earlier. As Ms Chalmers says, it is sensible to deal with these issues now, so that the parties know where they are in advance, rather than leave it until trial. In relation to (1), Ms Chalmers says there are reasonable grounds to consider that the statement of instructions to Mr Cutting is inaccurate or incomplete. Accordingly, the discretion conferred by rule 35.10(4) to order disclosure of instructions is engaged. I bear in mind two things. The first is that rule 35.10(3) does not require the expert’s statement of instructions to be complete, but only to state “the substance of all material instructions, whether written or oral…” (emphasis supplied). The second is that the test laid down by the rule is not whether the court is satisfied that the statement of instructions in fact was inaccurate or incomplete, but instead only whether it is satisfied that there are reasonable grounds so to consider it.
    1. In this connection, I was referred to the decision of the Court of Appeal in Lucas v Barking, Havering and Redbridge Hospitals NHS Trust [2004] 1 WLR 220. This was a claim for personal injuries said to have been caused by the defendant’s negligence. The claimant’s expert reports listed documents which had been supplied to the experts. The defendant applied for the production of two of them. The master made the order sought, holding that they were not part of the instructions within the meaning of rule 35.10(3), and therefore it was not necessary to satisfy the test in rule 35.10(4) before making the order. The claimant appealed, and the Court of Appeal reversed the decision of the master.
    1. Waller LJ (with whom Mantell and Laws LJJ agreed, although Laws LJ added a few comments of his own) said:
“31. … It seems to me that CPR 35.10(4) is designed primarily to give protection to a party who would otherwise have waived privilege by being compelled to set out matters in an expert’s report. It is also designed so far as possible to prevent lengthy arguments as to whether there has been a waiver of privilege either prior to the trial or indeed at trial leading to an entitlement to further disclosure.
[ … ]
34. … Material supplied by the instructing party to the expert as the basis on which the expert is being asked to advise should in my view be considered as part of the instructions and thus subject to CPR 35.10(4).”
      1. Ms Chalmers first of all relies upon the terms of Mr Cutting’s letter itself. They refer to “comments”, “suggestions” and “requests” relating to the draft joint statement of the experts. She also relies upon the terms of Mr Charlesworth’s second witness statement, dated 14 June 2022, where, at paragraph 13, he explains that the first part of Mr Cutting’s letter “included his comments in respect of an aide memoire my firm had sent to him in connection with the preparation of the expert’s joint statement in these proceedings”. Ms Chalmers points out that there is no reference to these comments, suggestions and requests, or to the aide memoire, in either the joint statement or Mr Cutting’s own report. (I have already set out the relevant extracts above.) She submits accordingly that the court should be satisfied that there are reasonable grounds for considering that Mr Cutting’s statement of instructions is incomplete. On the assumption that she crosses the threshold for the discretion to arise, she further submits that it would be appropriate in this case to exercise it.
    1. Mr Crowley made two main submissions to the effect that the defendant’s application was misconceived. First of all, he submitted that communications made to the experts for the purposes of their joint statement were not material communications for the purposes of rule 35.10(3). Secondly, he submitted that Mr Cutting’s statement of his instructions was not incomplete. He amplified the first submission by saying that an expert’s instructions to prepare his report did not extend to every communication to him. In support of this submission, he referred to several paragraphs in Lord Woolf’s Final Report on Civil Justice:
“31. … The point has been made that experts must be free to submit drafts to clients and their legal advisers, so that factual misconceptions can be corrected. A further that a great deal of time could be wasted if all these documents were disclosable, because the opposing party would have to comb through the various versions of a report to identify any changes… Another possibility is that lawyers and experts might begin to subvert the system by avoiding written communication in favour of off the record conversations.
32. I accept, in the light of these arguments, that it would not be realistic to make draft experts’ report disclosable. I do not, however, consider that privilege should apply to the instructions given to experts. …
33. Under the new system, transparency of instructions to experts will be particularly important. … I therefore recommend that expert evidence should not be admissible unless all written instructions (including letters subsequent upon the original instructions) and a note of any oral instructions are included as an annex to the expert’s report.”
    1. Mr Crowley also referred to the decision in Lucas v Barking, Havering and Redbridge Hospitals NHS Trust, in particular at [42], where Laws LJ said:
“As it seems to me the key to the case, and to the sense to be attributed to the term ‘instructions’ in CPR 35.10(3) and (4), is the imperative of transparency, a general theme of the CPR but here specifically applied to the deployment of experts’ reports. Thus the aim of CPR 35.10(3) and (4) is broadly to ensure that the factual basis on which the export has prepared his report is patent. That approach demands a wide reading of the term ‘instructions’ … “
And also at [34], where Waller LJ said:
“Material supplied by the instructing party to the expert as the basis on which the expert is being asked to advise should in my view be considered as part of the instructions and thus subject to CPR 35.10(4).”
    1. He submitted that solicitors’ comments on a draft report were not part of the instructions to the expert. They were simply routine communications during the conduct of the case. Moreover, he said that Mr Cutting’s report set out a complete statement of his instructions. In this respect, he referred to the Lucas case at [35]-[36] where Waller LJ said:
“35. There is however in this court an alternative string to the defendants’ bow. They say that it must follow that the experts in this case have not stated ‘the substance of all material instructions…’. Thus they say there has been a failure to comply with CPR 35.10(3) and an order for disclosure of the statement and the report should be made under CPR 35.10(4).
36. This submission as it seems to me misunderstands the relationship between CPR 35.10(3) and CPR 35.10(4). The obligation under CPR 35.10(3) is to disclose the substance of all material instructions. The protection under CPR 35.10(4) relates to ‘any specific document’ and ‘questioning in court’ unless the statement of instructions given under paragraph (3) is inaccurate or incomplete. There is no requirement to set out all the information contained in the statement or all the material that has been supplied to an expert. The only obligation on the expert is to set out ‘material instructions’. But the protection applies to any particular document and any particular question over any area, and has to do so because disclosure of part of privileged material by implication when deployed may waive other privileged material.”
    1. He also referred to the statement of Laws LJ that:
“43. There is a plain impact on the scope of legal professional privilege, and thus a degree of protection against the loss of privilege is given by the restrictions on disclosure provided for by 35.10(4). I think it a premise of the arrangements constituted by 35.10(3) and (4) that in the ordinary way the expert is to be trusted to comply with 35.10(3): the effect of the 35.10(4) restrictions is that the party on the other side may not as a matter of course call for disclosure of documents constituting the expert’s instructions as a check to see that 35.10(3) has been fulfilled. There must be some concrete fact giving rise to ‘reasonable grounds’ within the closing words of 35.10(4). It is unsurprising that the expert is thus to be trusted; it is of a piece with his overriding duty to help the court (CPR 35.3). Overall, 35.10(4) in my view strikes an important balance between on the one hand the protection of the party whose privilege is lost, and on the other the vindication of 35.10(3) where there is a real question-mark as to its fulfilment.”
    1. He further submitted that the report of Mr Cutting set out the factual basis for his opinions. In any event, it was the question what was material for the report, and not what was material for the joint statement. In this respect, the claimant referred to Waller LJ’s statement at [36] (cited above). He also pointed out that Mr Pither, the expert for the defendant, simply referred to his own written instructions. He did not mention the joint statement at all. So it was hardly fair to criticise Mr Cutting for not doing so.
    1. I agree with Mr Crowley that not every communication between experts and those instructing them is part of their “instructions” for the purposes of rule 35.10(3). At the same time, as Laws LJ said in the Lucas case, the aim of that rule is to ensure that the “factual basis” for the expert’s opinion evidence is apparent to the reader, and therefore a “wide reading” of the term “instructions” is needed. The question is where the line is to be drawn. It seems to me that the key lies in the words “factual basis”. The expert is a witness of opinion evidence, and not (or not primarily) of fact. Typically, the expert takes the facts from others. But if you change the facts, you may change the expert opinion. So knowledge of the facts, or assumptions of fact, on which the expert acts is fundamental to the direction and operation of the opinion. In my judgment, what rule 35.10(3) and (4) is concerned with is the question of the factual (and, I may add, sometimes the legal) basis for the opinion. These are matters which the expert cannot know him- or herself, but for which reliance must be placed on others.
    1. Whether the expert is then independent of the instructing party in giving an opinion is a quite different matter from the facts on which the opinion is based. That is governed, not by CPR rule 35.10(3), but by CPR rules 35.2, 35.10(1), Part 35 PD para 2.1, and the TCC Guide para 13.6.3. I see no reason to construe the words in rule 35.10(3) as requiring the expert to state the substance of all communications with those instructing him or her which go beyond providing the facts or factual (or indeed legal) assumptions for the opinion. If that is so, the power of the court to order disclosure of a specific document will not be engaged merely because the court is satisfied that there are reasonable grounds to consider that the statement of instructions does not refer to such communications.
    1. In relation to the application for the disclosure of the aide memoire, the question therefore is on what side of the line the aide memoire falls. Is it something setting out a factual or legal basis for the opinion of the expert, or is it something else, such as comments on a draft report or statement? In the first case, it would be part of the instructions, not privileged, but disclosable only if ordered under rule 35.10(4). In the second, it would not be part of the instructions, and would remain privileged unless and until privilege were waived, which would not happen unless it were deployed before the court, and not merely referred to. The problem is that, not having seen it, it is impossible for me to tell from the description alone, and therefore (for these purposes) I cannot be satisfied that it is part of the expert’s instructions. That conclusion means that I must proceed on the basis that it does not fall under the rule 35.10 regime at all, and I have no power to order its disclosure under that rule.
    1. On the other hand, in my judgment, there is nothing in rule 35.10(4) to prevent a party cross-examining the other party’s expert on such an aide memoire or on other communications which go beyond providing the facts or factual (or indeed legal) assumptions for the opinion. What would prevent that are the rules of privilege, and the trial judge’s ordinary case management powers. Here, however, the witness statement referring to the aide memoire was never covered by privilege, and any privilege that there was in the letter of 3 May 2022 has been waived. Given what is stated in the letter, the reference in Mr Charlesworth’s witness statement to an “aide memoire”, and the unresolved concerns which the defendant expressed about the independence of the expert, it seems to me that there is a proper basis for the cross-examination of Mr Cutting on these matters, although as I say rule 35.10(4) in my judgment has nothing to do with it.
    1. I may add that at present I see no basis for reaching the same conclusion in relation to the claimant’s other expert, Mr Pryce. The fact that there is a proper basis for cross-examining one expert on his independence does not by itself raise any presumption of such a basis in relation to another expert, and there is no material before me in relation to Mr Pryce to raise any suggestion of compromised independence.
  1. Accordingly I refuse to order disclosure of the aide memoire, or of any “comments”, “suggestions” and “requests” in relation to the experts’ joint statement or Mr Cutting’s report. On the other hand, but subject to any contrary direction of the trial judge, the defendant may cross-examine Mr Cutting (but not Mr Pryce) in relation to any such aide memoire, “comments”, “suggestions” or “requests”.