The reason the court asks for a psychiatric or psychological opinion is that the expert has specialist training (based in the confidence of patients and research subjects) and clinical knowledge (that demands access to information that the patient has provided under the impression of confidentiality, either directly to the expert or to other experts, who have entered it into files). Being a qualified health professional also brings credibility and power imbalance, making it difficult for the person described to question the expert’s opinion.
Not doing harm is our first duty. How is that possible when giving expert opinions in situations where we have no control over how the expertise is used, disseminated or understood? Instead, I think that we should use our scarce resources to develop good health services to incarcerated or otherwise sentenced persons, evidence-based treatments for aggressive behaviours and public mental health education.