Ken Pope brought attention to an article by Thomas G. Gutheil in the Psychiatric Times re: psychiatrists as expert witnesses - The new issue of Psychiatric Times includes a short article: “What Are Best Practices for Psychiatrists When Serving As Expert Witnesses?” 

Here are some excerpts: Although a “fact witness” is constrained to testify only to what was observed by the 5 senses, the “expert witness” is permitted to draw inferences and conclusions from other sources— hospital records, other experts’ examinations, basic principles, and so on. In a given context, a fact witness may testify, “I saw the defendant run through a red light,” whereas an expert might testify, “This doctor’s treatment of the plaintiff fell below the standard of care of the average prudent physician, causing the damage described.” 

The expert serves as a consultant to the court and offers opinions on subject matters that are beyond the scope of knowledge of the jury. 

The single most important point is first to understand—and accept—that the courtroom is not a clinical space. Your efforts are not for a patient’s well-being, but to inform the court by providing an opinion, usually about an examinee; the latter may be harmed by your testimony, but you are held to the truth, come what may. 

This expert role requires you to abide by courtroom rules, especially the Socratic model of question and answer. 

…….Third, experts must not only know the case cold, but also be prepared to meet challenges to the provided opinion, in the form of cross-examination, the latter of which is aimed at impeaching the expert’s testimony and weakening the expert’s credibility. Because every case has 2 sides, testifying experts should not take impeachment efforts personally but should realize that the adversarial structure of the law requires both sides being addressed and tested.

…..Sixth, turn off your cell phone before taking the stand. Judges can get annoyed at your phone going off mid-testimony, as this may seem to place your importance over the judge’s. 
One of the great and inescapable disappointments of testifying is that you may not be able to get your point across or to present your full opinion because of sustained objections or lawyer shenanigans. Swallow the bitterness, and accept that the system is not in your control. A great scholar once noted, “The expert witness is a hood ornament on the vehicle of litigation, not the engine.”

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