The instructions contained in this guidance are designed to provide a practical guide to preparing expert evidence and to provide guidance on the disclosure obligations of expert witnesses instructed by the investigator and/or the Crown Prosecution Service (the Prosecution Team). These instructions will assist expert witnesses, investigators and prosecutors to perform their duties effectively fairly and justly, which is vitally important to the integrity of the criminal justice system.

CPS HQ and Areas receive frequent requests to recommend an expert witness for the purpose of providing expert reports and opinion evidence in a specialised field. Frequent requests are also received for access to or the existence of a CPS Register of Experts.