What is the diminished capacity defense?

The diminished capacity defense, which addressed an accused's "general capacity or ability to form a specific intent or harbor a mental element of an offense," was abolished in 1982. (People v. Visciotti (1992) 2 Cal.4th 1, 56, 5 Cal.Rptr.2d 495, 825 P.2d 388; 22, subd. (a), 25, subd. (a), 28, subd. (a) ⁴.) Thus, evidence of voluntary intoxication or mental disorders may no longer be used as an affirmative defense to a crime. (People v. Saille (1991) 54 Cal.3d 1103, 1111-1112, 2 Cal.Rptr.2d 364, 820 P.2d 588.)

Such evidence is admissible, however, solely to negate an element of the crime which must be proven by the prosecution. (People v. Visciotti, supra, 2 Cal.4th at pp. 56-57, 5 Cal.Rptr.2d 495, 825 P.2d 388.) At the time of trial, section 22, subdivision (b), provided: "Evidence of voluntary intoxication is admissible solely on the issue of whether or not the defendant actually formed a required specific intent, premeditated, deliberated, or harbored malice aforethought, when a specific intent crime is charged." (Italics added.) ⁵

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