The expert witness in forensic psychiatry.

Forensic psychiatry operates at the interface of the Justice and Health systems and has been defined as: "That branch of psychiatry which requires special knowledge and training in the law as it relates to the mental state of the offender, or alleged offender" [1]. As a consequence of working in this area, psychiatrists are often called into court to give evidence as "expert witnesses". This article examines some of the professional and legal issues involved in providing expert testimony. Secondly, it aims to outline some practical guidelines for giving evidence in the court-room. The predominant focus is on criminal, rather than civil, proceedings in which the forensic psychiatrist gives expert testimony; however much of the information is also relevant to other psychiatrists and psychologists undertaking this role in the legal arena.