In Trinsic Collagen Ltd v Procoll Ltd [2026] EWHC 1793 (Ch), the court criticised the way additional information had been provided to the claimant’s experts and then relied on without being clearly identified in the reports, or in one instance the joint statement.

The issue was not that the experts had spoken to the client. It was that the factual basis of their conclusions was not always transparent.

For an expert report to assist the court properly, the reader should be able to see the route from the facts and assumptions, through the analysis, to the opinion reached. That means being clear about material obtained through discussions, site visits, correspondence or subsequent instructions, especially where it influences the expert’s reasoning.

The Academy’s own guidance reflects the same principle. An expert report should contain a concise statement of the facts and assumptions used, followed by the expert’s analysis and opinion, with fact and opinion clearly distinguished.

A useful question before signing a report is this: could another expert, or the judge, identify every material fact and assumption on which my conclusion depends? If not, the report may need another look.

The Academy’s Model Form of Expert Report also reflects this approach.