CAL. PEN. CODE § 25 : California Code - Section 25
Search CAL. PEN. CODE § 25 : California Code - Section 25
(a) The defense of diminished capacity is hereby abolished. In a criminal action, as well as any juvenile court proceeding, evidence concerning an accused person's intoxication, trauma, mental illness, disease, or defect shall not be admissible to show or negate capacity to form the particular purpose, intent, motive, malice aforethought, knowledge, or other mental state required for the commission of the crime charged.
(b) In any criminal proceeding, including any juvenile court proceeding, in which a plea of not guilty by reason of insanity is entered, this defense shall be found by the trier of fact only when the accused person proves by a preponderance of the evidence that he or she was incapable of knowing or understanding the nature and quality of his or her act and of distinguishing right from wrong at the time of the commission of the offense.
(c) Notwithstanding the foregoing, evidence of diminished capacity or of a mental disorder may be considered by the court only at the time of sentencing or other disposition or commitment.
(d) The provisions of this section shall not be amended by the Legislature except by statute passed in each house by rollcall vote entered in the journal, two-thirds of the membership concurring, or by a statute that becomes effective only when approved by the electors. 26. All persons are capable of committing crimes except those belonging to the following classes:
One--Children under the age of 14, in the absence of clear proof that at the time of committing the act charged against them, they knew its wrongfulness.
Two--Persons who are mentally incapacitated.
Three--Persons who committed the act or made the omission charged under an ignorance or mistake of fact, which disproves any criminal intent.
Four--Persons who committed the act charged without being conscious thereof.
Five--Persons who committed the act or made the omission charged through misfortune or by accident, when it appears that there was no evil design, intention, or culpable negligence.
Six--Persons (unless the crime be punishable with death) who committed the act or made the omission charged under threats or menaces sufficient to show that they had reasonable cause to and did believe their lives would be endangered if they refused.