Moylett v Geldof & Anor

Expert evidence should generally be admitted where it contains genuine expertise, even if parts also address matters for the court or express an ultimate conclusion. In all but clear cases, the court should avoid excising individual passages from an expert report. The trial judge should consider the report as a whole, disregard material outside the expert’s proper field, and determine what weight to give the admissible material. Evidence reporting what other specialists told the expert is not itself expert opinion evidence, although the expert may rely on demonstrations or information received in forming an independent expert opinion.

The claimant applied for a ruling on the admissibility of parts of an expert report concerning whether music was composed on a guitar or piano. The report referred to demonstrations and comments by two professional guitarists, although permission had been granted for only one expert. It also expressed an opinion on the ultimate issue of which party was more likely to have composed the music.

The court considered whether those matters rendered the report inadmissible or required passages to be removed before trial.

1. Approach to expert reports. The court applied the guidance in Hoyle v Rogers & Anor [2014] EWCA Civ 257. Opinions on disputed facts that do not require expertise are inadmissible and should receive no weight. However, where such material is intertwined with genuine expert evidence, it is generally disproportionate to edit the report. The trial judge should see the whole report and use only the parts that reflect genuine expertise.
2. References to the guitarists. Mr Protheroe was entitled, and effectively obliged, to record that he had obtained demonstrations from the two guitarists. He could form his own expert opinions from those demonstrations. The guitarists’ own statements could not be relied on as expert opinion evidence, but the report was otherwise admissible insofar as it dealt with them.
3. Ultimate conclusion. The opinion that the music was more likely to have been composed on a guitar or piano was admissible and relevant expert evidence. The fact that it addressed the ultimate conclusion did not justify exclusion at this stage. Its weight was for the trial judge, and it might properly be the subject of an expert reply.
4. Result. The guitarists’ statements were not to be relied on as expert opinion evidence. The remaining challenged material was admissible. No excision of the report was required.