There is no automatic right for a party to adduce expert evidence in legal proceedings. Permission of the Court is required. A recent case illustrates how the Court can revoke such permission if the Court has no confidence in an expert’s objectivity. 

The facts

In a group action nuisance claim (emission of dust, noise and odour from a wood processing and manufacturing plant) the Claimant and Defendant were granted permission to appoint their own experts in the field of dust dispersion modelling and dust analysis. Expert reports were exchanged in April 2021 and joint discussions began in May 2021. Between May to November 2021 the Claimant’s expert had sent draft versions of the expert joint statement to his instructing solicitors inviting their input. The solicitors made suggestions on the substantive content of the joint statement.

The expert’s obligation

The obligations are framed by CPR35.3, PD35 paragraph 2.1 and 2.2. In essence, the role of the expert is to help the Court and this duty overrides any obligation to the person from whom instructions are obtained. The evidence must be uninfluenced and objective opinion in relation to matters within the expert’s expertise.

Request for solicitor input: Once the experts had begun their joint deliberations the solicitor should not have been permitted to influence the substantive content of the joint statement. The influence of the solicitor on the joint statement was a serious transgression of the expert’s independence.

The limit of solicitor input

A narrow exception has been recognised where a solicitor might be permitted to see the joint statement before signature to ensure that it is not tainted by some material misunderstanding of law or fact (BDW Trading Ltd v Integral Geotechnique (Wales) Ltd [2018] EWHC 1915 (TCC)). If the solicitor is to raise anything about the joint statement this must be done on a transparent basis involving the experts, parties and Court. The narrow exception falls short of giving an instructing solicitor the opportunity to influence the substantive content of the joint statement. If a solicitor goes beyond this narrow exception, permission for evidence from the expert will be in jeopardy.

Revocation of permission

The point in issue was the appropriate sanction. The Senior Master revoked permission of the expert causing the wasting of the fees of over £250,000. Permission was granted for a new expert. The input from the solicitor went beyond correcting typographical errors. Revoking the permission of the expert was not a disproportionate sanction where the obligations of the expert had been undermined.


It is crucial that experts and solicitors respect the objectivity on the expert arising from CPR 35.3. An expert must never permit the joint statement to be influenced by the instructing party or their solicitor. If the expert does so, a Court might consider the expert to be advocating the client’s case rather than maintaining objectivity under their primary obligation to the Court.

Case: Patricia Andrews and others v Kronospan Limited [2022] EWHC 479 – Senior Master Fontaine

For further information please contact Philip Eyre