Whether voluntary intoxication or mental disorder may still reduce an intentional killing from murder to nonstatutory voluntary manslaughter by negating malice aforethought.
Holding
No. The 1981 legislation abolishing diminished capacity, especially the amendment to Penal Code section 188, eliminated diminished-capacity or nonstatutory voluntary manslaughter based on voluntary intoxication or mental disorder.
Reasoning
Before the 1981 reforms, California’s diminished-capacity doctrine allowed evidence of intoxication or mental abnormality to show that a legally sane defendant lacked a particular mental state. Under People v. Conley and People v. Poddar, malice aforethought was expanded beyond an intent to kill: it included awareness of one’s legal duty to govern conduct and the ability to act in accordance with that duty. An intentional killing could therefore be reduced to voluntary manslaughter if intoxication or mental illness prevented the defendant from possessing that enlarged form of malice.
The Legislature responded to this doctrine by enacting Penal Code sections 22, 28, and 29 and, through Proposition 8, section 25. Those provisions abolished diminished capacity as a defense and barred evidence of intoxication or mental disorder to show that a defendant lacked the capacity to form a mental state. They nevertheless permit such evidence on the factual question whether the defendant actually formed a required specific intent, premeditated, deliberated, or harbored malice.
Most importantly, the same legislative package amended section 188’s definition of malice. The amendment provides that when an intentional killing is committed with express or implied malice as section 188 defines it, no additional mental state is necessary; it expressly rejects Conley and Poddar’s requirements of awareness of legal duty and capacity to comply with it. For express malice, an intent unlawfully to kill is now the same thing as malice aforethought.
Thus, once the factfinder finds an intent unlawfully to kill, express malice is established. Intoxication or mental illness may still bear on whether the defendant actually formed that intent, but it cannot separately negate an expanded, Conley-style conception of malice. If the evidence creates reasonable doubt about intent to kill and does not establish implied malice, the killing may be involuntary manslaughter or result in acquittal—not diminished-capacity voluntary manslaughter.
Section 192’s ordinary voluntary-manslaughter rule remains intact. An intentional killing may still be mitigated to voluntary manslaughter when it occurs in a sudden quarrel or heat of passion upon legally adequate provocation. But that statutory mitigation does not preserve the former nonstatutory mitigation based solely on voluntary intoxication or mental impairment.
This construction does not violate due process. The Legislature may define the mental elements of crimes and may eliminate a mens rea theory that is no longer part of the statutory definition. It may not prevent a defendant from disputing a mental state that remains an element, and Saille remained free to use evidence of intoxication to contest whether he actually intended unlawfully to kill.