A senior judge has used a judgment to send the message to solicitors that partisan expert witnesses will not be tolerated. The warning  by The Honourable Mr Justice Fraser appears in a 428-paragraph quantum judgment in Imperial Chemicals Industries Ltd v Merit Merrell Technology Ltd.

The dispute, over works performed at a paint manufacturing unit from 2012 to 2015, included quantum experts being called for both parties. But the judge described a joint statement by them as a ‘most unhelpful document’ which essentially amounted to a repeat of each expert’s view.

A second expert called by ICI, a specialist in forensic accounting, was also criticised in the judgment for ‘direct factual inaccuracy’ concerning his opposite number, while he was also hindered by a lack of communication to him from ICI’s solicitors about potential further documents he could review.

The judge concluded overall that each of ICI’s experts was ‘not sufficiently independent’ of the party who instructed them, and that the evidence of the other side’s experts should be preferred.

This matched his conclusion on experts called in the previous liability trial where Fraser noted that ‘an expert’s role is not to decide issues of fact themselves, and choose what facts to believe and what not to believe’.

Whether the similar lack of independence was coincidence or not, he continued, it was a ‘matter of concern’ that in a case worth £10m there should be ‘such a preponderance of partisan experts’.

The judge said: ‘There are some jurisdictions where partisan expert evidence is the norm. For the avoidance of any doubt, this jurisdiction is not one of them. Not only experts, but the legal advisers who instruct them, should take very careful note of the principles which govern expert evidence.’

Fraser stressed that experts of the same discipline should have access to the same material and no party should provide its own independent expert with material solely held by them.

He said it was a matter for the court, not the expert, about which version of the facts they prefer, and experts’ meetings before trial should be given greater importance for saving expense and time.