Vilca & Ors v Xstrata Ltd & Anor

Where a party seeks to replace an expert and requires the court’s permission or an extension of time, the court has power to require disclosure of the substance of the earlier expert’s opinion. The usual purposes are to discourage undesirable expert shopping and to ensure that useful information is available to the court and the opposing party. The condition is not automatic. The court must exercise its discretion in accordance with the overriding objective. Where replacement is caused by illness, there is no abuse of process, and disclosure would add little or create disproportionate practical difficulties, the condition may properly be refused.

Twenty-two Peruvian nationals brought personal injury claims arising from a protest at a Peruvian copper mine. The defendants’ Peruvian-law expert withdrew because of ill-health shortly before exchange of expert evidence. The defendants sought an extension of time to instruct a replacement expert.

The claimants accepted that replacement evidence should be permitted but sought disclosure of the reports or draft opinions of the earlier experts as a condition. The issue was whether that condition should be imposed in the exercise of the court’s case-management powers.

1. The defendants’ need for an extension of time brought the court’s case-management powers into play. Those powers included requiring disclosure of the substance of prior experts’ opinions as a condition of permitting replacement evidence.
2. The discretion had to be exercised in accordance with the overriding objective. The court should consider the twin concerns of discouraging undesirable expert shopping and ensuring that useful information was available to the court and the opposing party. Those considerations made disclosure usual where they were present, but did not create an inflexible rule.
3. There was no sound basis for suspecting expert shopping or abuse of process. Professor Revoredo had withdrawn because of ill-health. The earlier change from Mr Amado to Professor Revoredo had been made to improve the quality and weight of the evidence, without evidence that an unfavourable opinion had been discarded.
4. The claimants had their own expert and could identify errors or omissions in the replacement report through expert meetings, joint statements and trial. Disclosure of the draft report would probably add no useful information and risk distracting the trial with disputes about draft passages and related communications.
5. The balance, taking account of the overriding objective and the need for a fair, effective and expeditious trial, favoured refusing the condition. The necessary extension was granted without requiring disclosure of the earlier experts’ reports.