Sometimes it makes sense for disputing parties to agree a joint expert. That's all very well until the expert says something one side disagrees with …
Since the introduction of the Civil Procedure Rules, the court-appointed expert has become a popular animal. Where the claims are relatively small, the cost to the parties of each retaining an expert can disproportionate to what is at stake, making it sensible for parties to agree to a joint expert. But, as a recent case shows, it can all go wrong.

The idea of a joint expert is fine provided that the expert is good in their field and sufficiently independent to command respect from both parties. This is important because the judge is likely (although not bound) to accept the joint expert's evidence. The problem with some experts is that they gain a reputation, justified or not, that they favour a particular position. Many claims consultants are seen, unsurprisingly, as contractors' men; employers might prefer not to have one as a joint expert. Some architect experts seem to be wheeled out regularly to support negligence actions against their fellow professionals. Whether valid or not, it can undermine confidence in their independence.

Even where the parties have agreed on the appointment of a joint expert, what happens if the expert produces a report that one party or the other finds unacceptable? The court has the power to permit that party to call its own expert, but will exercise its discretion to do so sparingly.

The case of Layland vs Fairview New Homes shows how things can go wrong. Mr and Mrs Layland bought a flat in Lewisham, south-east London, from Fairview. In court they alleged that they had bought the flat relying on a misrepresentation that Fairview knew of nothing untoward relating to the use and enjoyment of the flat. In fact, the local council had, before the purchase, granted itself planning permission to build a power and incineration plant nearby, but the council also told the Laylands that it was not aware of proposals for any adjoining site that adversely affected the flat.

The problem is that some experts gain a reputation, justified or not, that they favour a particular position

The Laylands sued Fairview for misrepresentation and the council for negligent misstatement; their damages claim was largely for capital diminution relating to the nearby incineration plant. The court appointed a joint expert who reported that there was no diminution. The defendants, encouraged by this turn of events, applied to have the case dismissed on the basis that the Laylands could not recover any damages if the only expert was against them. To counter this, the Laylands submitted newly obtained reports from two further experts, to which the judge did not attach much weight; he found in favour of the defendants. The Laylands appealed.

The court has discretion to allow a party to call its own expert, but must consider all the circumstances, such as the value of the claim and the grounds on which the joint expert's views are being challenged. The judge in the lower court had properly concluded that the Laylands should not be permitted to call their two new experts: the amount in issue was small, the joint expert had been appointed without objection and was appropriately experienced, unbiased and not unreasonable in his analysis; the two new experts had not come up with hard facts that the joint expert had not taken into account, and one of the two new reports was unimpressive and of little assistance.

However, Mr Justice Neuberger held that considerable circumspection must be invoked before a court should dismiss a claim in this way, even if the claim is for a small sum, looks weak or is being pursued unattractively or ineptly. The the joint expert's views needed to be tested at trial and not summarily, and the lower judge could not properly have concluded that the Laylands had no realistic prospect of establishing some capital diminution at trial by way of cross-examination of the joint expert. The Laylands therefore won the appeal and a trial will follow.