Gary Pickett v David Balkind

Where privileged or confidential material is disclosed by mistake, an injunction is exceptional. The court may restrain its use where the recipient knew, or a reasonable solicitor would have appreciated, that a mistake had occurred, subject to the equitable circumstances and any prejudice or reliance. Deliberate disclosure to an opponent ordinarily waives privilege, even where disclosure serves only an interlocutory purpose. An expert’s instructions comprise the factual or legal basis of the opinion, not every communication about drafting an expert report or joint statement. Where an expert report relies on an earlier undisclosed report, the reference may amount to deployment and waiver. A party cannot retain the forensic advantage of that reliance while withholding the underlying document.

The claimant brought a tree-root subsidence claim concerning damage to his property. Before trial, applications arose from the claimant’s disclosure of an unredacted letter from his structural expert, Mr Cutting, and references by the claimant’s arboricultural expert, Mr Pryce, to an undisclosed report by Prior Associates.

The claimant sought to restrain use of Mr Cutting’s letter. The defendant sought permission to use it, disclosure of materials said to comprise Mr Cutting’s instructions, permission to cross-examine him, and production of the Prior Associates report. The central issues were waiver of privilege, the scope of CPR rule 35.10(4), and the effect of deploying an expert report which relied on an undisclosed document.

1. Injunction concerning Mr Cutting’s letter. The principles in Al Fayed v Commissioner of Police of the Metropolis [2002] EWCA Civ 780 applied although the letter had been sent in support of an adjournment application rather than disclosed for inspection under CPR rule 31.20. Once a privileged document had been shown to the opponent, relief was generally too late, but the court retained an equitable jurisdiction where justice required, including fraud or an obvious mistake. The relevant circumstances included the recipient’s conscience, whether the mistake was obvious, reliance, prejudice, fairness and public policy.
2. The claimant’s solicitor had made an error, but the defendant’s solicitor neither realised nor ought reasonably to have realised that a mistake had occurred. The defendant had also relied on the letter in raising a legitimate concern about compliance with the TCC Guide. No injunction was therefore granted. The court held that privilege had been waived in the whole letter. Deliberate disclosure to the opponent waives privilege even where the disclosure is made for an interlocutory purpose. The letter could not be divided so as to preserve privilege in selected passages.
3. Expert instructions and cross-examination. Under CPR rule 35.10(3) and (4), the relevant instructions are those supplying the factual or legal basis of the expert’s opinion. The rule does not require disclosure of every communication about drafting a report or joint statement. The court could not order disclosure of the aide memoire because, without seeing it, it could not be satisfied that it formed part of the instructions. However, privilege and ordinary case-management powers did not prevent cross-examination about communications bearing on Mr Cutting’s independence. Permission was given to cross-examine Mr Cutting, but not Mr Pryce.
4. Prior Associates report. Mr Pryce had relied on the earlier report’s conclusion, rather than merely mentioning it. The claimant had deliberately served his report and thereby adopted that deployment. Any privilege had consequently been waived, and the claimant could not withdraw the report or substitute a supplemental report to avoid the consequences of its reliance on the earlier report. The defendant was ordered to be given the report so that it could check that the claimant was not cherry-picking its contents.
5. The injunction was refused; disclosure of the aide memoire and associated comments was refused; permission was given to cross-examine Mr Cutting; and production of the Prior Associates report was ordered.