## Facts

- Ronald Dennis Wolff, age 15, killed his mother.
- The juvenile court found Wolff not a fit subject for juvenile treatment and remanded him for adult criminal proceedings.
- Wolff entered a single plea of not guilty by reason of insanity, admitting the basic act but contesting legal responsibility.
- Court-appointed psychiatrists examined Wolff; after a competency inquiry, the court found him mentally ill but competent to assist counsel.
- At the sanity trial, multiple psychiatrists testified Wolff suffered schizophrenia and that the killing resulted from an “irresistible impulse,” but other evidence suggested he understood what he was doing and that it was wrong.
- The jury found Wolff legally sane at the time of the homicide.
- By stipulation, the court determined degree of murder on the trial evidence and probation report, found first-degree murder, imposed life imprisonment, and recommended hospital placement for the criminally insane.

## Issues

1. Whether substantial evidence supported the jury’s finding of legal sanity despite unanimous psychiatric testimony favoring insanity.
2. Whether jury instructions on the presumption of sanity and the presumption of continuance of prior “permanent” insanity were conflicting and prejudicial.
3. Whether the record supported first-degree murder, or instead required reduction to second-degree murder given Wolff’s youth and mental illness as bearing on premeditation and deliberation.

## Decision

- The court affirmed the jury’s sanity verdict, finding substantial evidence that Wolff knew the nature of his act and its wrongfulness.
- The court rejected claims of reversible instructional error, concluding the instructions as a whole properly explained presumptions and the defendant’s burden to prove insanity by a preponderance of the evidence.
- The court modified the judgment from first-degree murder to second-degree murder because the evidence, viewed comprehensively, did not adequately establish the deliberation and premeditation required for first-degree murder in light of Wolff’s mental condition.
- The life sentence remained in place, with the recommendation for psychiatric placement.

## Legal Principles

- California applied the M’Naghten test for legal insanity: whether the defendant did not understand the nature and quality of the act or did not know it was wrong.
- “Irresistible impulse,” standing alone, is not a separate legal test for insanity under M’Naghten.
- Even unanimous expert psychiatric testimony on insanity does not bind the trier of fact; the jury may weigh expert opinion against lay and circumstantial evidence, including the defendant’s conduct and statements.
- Severe mental illness and youth may bear on whether the prosecution proved the specific mental state elements for first-degree murder (willful, deliberate, and premeditated killing), even when the defendant is legally sane.

## Conclusion

The court upheld the jury’s finding that Wolff was legally sane under M’Naghten and found no prejudicial instructional error, but reduced the conviction to second-degree murder because the evidence did not sufficiently show premeditation and deliberation when Wolff’s serious mental illness and age were considered.


People v. Wolff, 61 Cal. 2d 795 (Cal. 1964)