Professional negligence claims require evidence that a professional owed a duty, failed to meet the required standard, and caused identifiable loss. The duty usually arises from a contract, such as an engagement letter, or from the professional relationship itself. The claimant must link the alleged error to the loss rather than relying only on an unsatisfactory outcome.
The retainer or engagement letter establishes the work the professional agreed to undertake, its limits, and any relevant terms. Other important records include instructions, emails, meeting notes, advice, draft documents, calculations, file notes and invoices. A clear chronology can show what information was provided, when decisions were made and where the alleged failure occurred.
Expert evidence is often required to assess whether the professional’s conduct met the standard expected from a reasonably competent practitioner in that field. The expert usually examines the instructions, the work completed and the alternatives available at the time. The assessment focuses on the information then available, not solely on the fact that the eventual result was adverse.
Evidence must address what would have happened if the professional had acted competently. This involves identifying the alternative step, transaction or decision and showing that it would probably have avoided or reduced the loss. Financial evidence can include valuation reports, management accounts, transaction documents, tax records, repair estimates and independent assessments. The claimant also needs to distinguish losses caused by the professional’s conduct from losses arising for other reasons, and to show reasonable steps taken to reduce the loss.
Harper James is a UK full-service commercial law firm advising businesses on the laws of England and Wales. In practice, a claim is usually prepared by preserving the relevant file, building a chronology, obtaining an initial expert view where appropriate, calculating loss and following the applicable pre-action procedure. Limitation periods depend on the legal basis and facts, so the date of the breach, discovery of the damage and any contractual terms require careful review before proceedings are issued.