Legal psychology is derived from scientific, psychological research of the law, legal institutions, and the people they affect. Legal psychologists apply basic cognitive and social principles and extrapolate them into issues involving the legal system.
Anyone with a professional interest in Law should acquire a basic understanding of the main areas of research relevant to the crossover of these two disciplines.
Clinical Psychology: As applied to law, this deals with issues of competency, the insanity defense, suspect, and offender profiling. These typically fall under forensic psychology.
Eyewitness Testimony: Once the primary focus of those concerned with legal psychology, along with jury decision making- courts are increasingly looking to more substantial forms of evidence. While eyewitness testimony is still heavily relied upon, the notion that eyewitness testimony can be taken as reliable evidence is rapidly losing support.
Expert Witnesses: Psychologists who are specially trained in legal issues are frequently called upon by legal parties to provide their professional opinion about the mental state of a witness, defendant, or plaintiff. Experts of this kind are usually asked to offer an appraisal of a defendant’s competence to stand trial, or about perceptions as to whether of not the person knew the crime at issue was, in fact, morally wrong.
Policy Making: Psychologists working in public policy centers can be influential in the formulation of legislative policy. They may be called upon by lawmakers to address issues of public health and the general welfare.
Advisory Roles: Legal psychologists may occupy advisory positions within a court system. They can advise judges or other decision makers about psychological findings relevant to a given case. Psychologists who act as court advisers provide similar input to psychologists acting as an expert witness but act in accordance with the expectations of the adversarial system.
Trial Consultants: Special training or certification is not needed to be a trial consultant though advanced degrees are welcomed. Some psychology academics are taken on as trial consultants at times when their expertise will be useful to a case.
Trial consultants can provide a range of services for lawyers, such as jury selection, or by performing “mock trials” using focus groups. Trial consultants can help organize testimony, prepare witnesses, and even arrange for the use of “shadow jurors” who observe as the trial unfolds in order to provide their input. There is a debate on whether trial consultants are protected under attorney-client privilege provisions, especially when a conflict of interest may arise.
Amicus briefs: An amicus brief contains an opinion backed by scientific citations and statistics about the state of mental illness, mental retardation, or brain damage of persons of interest for determining the quality of their possible testimony or responsibility for past deeds with which a legal proceeding is concerned.