Expert Psychiatric Evidence

Keith Rix, a British forensic psychiatrist, writes here with authority and detail about the range of forensic evaluations currently required by courts and tribunals in the United Kingdom. His text is enriched by examples from his practice and with quotes from judges, some of whom have not been slow to offer advice to the aspiring forensic psychiatrist: The area of expertise in any case may be likened to a broad street with the plaintiff walking on one pavement and the defendant on the opposite one. Somehow the expert must be ever mindful of the need to walk straight down the middle of the road and resist the temptation to join the party from whom his instructions come.¹ The judge did not mention what can happen to people who walk down the middle of the road, but Rix has some stories to tell.

Those who live where pavements are called sidewalks will notice that the forensic practice Rix describes differs from theirs in several respects. One is the routine inclusion by Rix of a methodology section in the psychiatric report. The United Kingdom has recently seen the publication of Law Commission proposals relating to evidentiary reliability in criminal trials.² Those proposals place considerable emphasis on sound methodology as a criterion for admissibility. They arose largely out of concern over evidence's going to guilt or innocence. In one case expert evidence had been offered to the effect that the odds against two unexplained infant deaths occurring in the same family made it likely that a crime had been committed.

Rix argues that it may now be time for psychiatric experts to describe their methodology, also. He suggests psychiatrists indicate in all of their reports that clinical practice depends on two types of knowledge: that for which there is sound scientific evidence and experience-based knowledge for which such evidence is lacking. “Indicate,” he suggests, “that in relying on both categories of knowledge you have done so in accordance with what would be regarded as a responsible body of psychiatric practice” (p 41). This raises substantial questions, it seems to me, about the role of the report and the duty of the expert to place it in proper context. The degree to which information of the type Rix describes is routinely provided in the United States is an under-researched area. I suspect that usual practice is to offer this type of explanation only when asked to do so in testimony.

Rix also makes a number of suggestions in other areas of forensic practice: the psychiatric expert should have a selection of curriculum vitae for different types of work (p 18); with proper notice that this is their practice, psychiatrists are entitled not to sign a report until they have been paid (p 23); reports should come with tables of contents, unless they are very short (p 39); it may be acceptable not to list in a report all of the materials one has seen where the defense is still considering what information to disclose to the prosecution (p 43); where the report of another expert is part of the material, the conclusion of the other expert should be commented on (p 48); and the expert should provide a diagnosis, even if not asked to (p 48).

Rix also makes an exception to the “don't answer a question you haven't been asked” rule where the subject is not having treatment that he ought to have: Whether asked to do so or not, make a recommendation for treatment that accords with the best practice of psychiatry, ask that this recommendation is passed on to the subject's ordinary medical attendant and ask to be informed that this has been done [p 48]. The requirement to act in the best interests of the person being assessed, Rix writes, ultimately outweighs any duty of confidentiality to the instructing party. The implied code of ethics is thus much closer to that of the practicing clinician than it is to the position that U.S. forensic psychiatry has adopted. Rix lists the principles of medical ethics applicable to the psychiatric expert witness as autonomy, beneficence, nonmaleficence, and justice.

Those U.S.-based psychiatrists who have wrestled with the terminology and case law of provocation and extreme emotional disturbance will be interested to read the description of the Criminal Justice Act 2009 of England and Wales and its introduction of the defense (I would prefer partial defense, since it only reduces murder to manslaughter) of loss of control. There is a discussion of the practice of holding discussions between experts, not just in family proceedings, but also in civil and criminal matters. U.S. experts will welcome, I suspect, the discussion of the role of the single joint expert and the changes to practice (for instance, in the copying of all communications to both sides) that working in this way entails.

The book is written with a refreshing frankness. Its advice on the fraught question of whether and how to address the ultimate issue before the court (to paraphrase Rix: note that it is, technically, none of one's business and then be prepared to say what one thinks) is particularly clear. As a result, for a book on a technical area of forensic psychiatry, Expert Psychiatric Evidence is an unusually easy read. It also has a very good index.

• © 2013 American Academy of Psychiatry and the Law