Jenkins v. U.S. (1962)

Synonyms

Admissibility of psychological evidence; Competence to testify

Historical Background

Vincent E. Jenkins was a defendant who mounted an insanity defense, introducing the testimony of psychiatrists and psychologists that he was suffering a mental disease (schizophrenia) at the time of a sexual assault. The trial court instructed the jury to disregard psychometric evidence on the grounds that psychologists were disqualified from testifying about mental disease because of a lack of medical training. The appeals court for the Second District reversed the trial court ruling, ordering the new trial to include psychological testimony and psychometric findings. The appeals court noted that a diverse array of nonphysicians (e.g., doctoral level toxicologists) regularly offered opinions. The majority opinion offered a two-pronged test of admissibility for psychologists’ testimony: (1). the actual experience of the witness and (2). the probative value of his opinion. This opinion implies...