When an expert witness steps away
When an expert witness has to step away from a case,
how much information has to be given about why?
In the case of Adams -v- Allen & Overy  All ER (D) 146 (Jul) Court: Ch D an expert witness decided part way through proceedings to remove himself. The case concerned the valuation of an area of land in Buckinghamshire. A dispute arose as to whether the value given had been much lower than the real value of the land. Expert witnesses were appointed but, despite mediation, no agreement could be reached. The claimant then commenced proceedings. In the pleadings, the claimant’s expert was not the same one as had been used previously. The defendants asked why the claimant had changed expert, and were informed that the original expert had declined to continue to act. At the case management conference, the master refused to permit the claimant to rely on the claimant’s new expert. He stated that, in the absence of a good reason from the original expert for not working, there was no possibility of changing the expert. The claimant appealed.
The two issues for decision were:
- whether the claimant ought to be allowed to instruct the new expert, and
- whether, if the claimant sought to rely on the new expert’s report, the original expert’s communications with the claimant’s instructing solicitors had to be disclosed.
The appeal was allowed.
The Court of Appeal decided that the master had erred in failing to address the practical effect of there being no good reason for the original expert’s withdrawal. Where an expert has been active from the pre-action protocol stage, a reason for his withdrawal has to be shown. However, the threshold will vary depending on the circumstances of the individual case. In this case, the claimant had given a reason for calling the new expert – that the original expert was unwilling to continue. It was far from certain that the original expert had to explain himself. In weighting the overall conduct of the parties, there was no evidence that the claimant had done anything improper. To allow the master’s order to stand ran the risk of unbalancing the trial.
In conclusion, the claimant was allowed to call the new expert and there was no need to reveal the original expert’s communications with the instructing solicitors.