California statute
Cal. Penal Code § 28
Current through 2025–2026 Regular Session (leginfo weekly dump, 2026-07-12)
Part of Title 1: Of Persons Liable to Punishment for Crime, California Penal Code.
Full text of Cal. Penal Code § 28
Statutory text current through the 2025–2026 Regular Session (leginfo weekly dump, 2026-07-12). This publication reproduces the official statutory text; it is not the official statutes of the State of California.
(a) Evidence of mental disease, mental defect, or mental disorder shall not be admitted to show or negate the capacity to form any mental state, including, but not limited to, purpose, intent, knowledge, premeditation, deliberation, or malice aforethought, with which the accused committed the act. Evidence of mental disease, mental defect, or mental disorder is admissible solely on the issue of whether or not the accused actually formed a required specific intent, premeditated, deliberated, or harbored malice aforethought, when a specific intent crime is charged. (b) As a matter of public policy there shall be no defense of diminished capacity, diminished responsibility, or irresistible impulse in a criminal action or juvenile adjudication hearing. (c) This section shall not be applicable to an insanity hearing pursuant to Section 1026. (d) Nothing in this section shall limit a court’s discretion, pursuant to the Evidence Code, to exclude psychiatric or psychological evidence on whether the accused had a mental disease, mental defect, or mental disorder at the time of the alleged offense.
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