Forensic psychiatrists work with courts in evaluating an individual's competency to stand trial, defenses based on mental diseases or defects (e.g., the "insanity" defense), and sentencing recommendations. There are two major areas of criminal evaluations in forensic psychiatry. These are Competency to Stand trial (CST) and Mental State at the Time of the Offense (MSO).
CST: This is the competency evaluation to determine that a defendant has the mental capacity to understand the charges and assist his attorney.
MSO: This gives the Court an opinion, and only an opinion, as to whether a defendant was able to understand what he/she was doing at the time of the crime.