Criminal Law and Procedure
Criminal Law and Procedure
This domain covers the intersection of psychology and criminal law. Candidates must understand key legal concepts: mens rea, actus reus, competency to stand trial (Dusky standard), insanity defense (M'Naghten, ALI, Durham), diminished capacity, and sentencing (e.g., death penalty, mitigation). Traps include confusing competency (present ability) with insanity (mental state at time of offense), misapplying the Dusky standard (e.g., requiring perfect understanding), and overlooking the difference between competency to stand trial and competency to waive rights. Another trap is assuming that a defendant with mental illness is automatically incompetent.
Worked example: A defendant with delusions believes the judge is conspiring against him. Under Dusky, the question is whether he has sufficient present ability to consult with his lawyer with a reasonable degree of rational understanding and a rational as well as factual understanding of the proceedings. If delusions impair his ability to assist counsel, he may be incompetent. Rule of thumb: competency is case-specific and functional, not diagnosis-based.
Key concepts: Dusky standard, M'Naghten, ALI, diminished capacity, mens rea, mitigation, competency vs. insanity.