The expert witness in psychology and psychiatry.

The involvement of psychologists and psychiatrists within the legal arena continues to grow rapidly but remains highly controversial. Extensive research on clinical judgement provides a scientific basis for clarifying the growing disputes about the values of such professional activities. Studies show that professionals often fail to reach reliable or valid conclusions and that the accuracy of their judgements does not necessarily surpass that of laypersons, thus raising substantial doubt that psychologists or psychiatrists meet legal standards for expertise. Factors that underlie the research findings and implications for courtroom testimony are discussed.