## Facts

- Smith was tried in the District of Columbia for first-degree murder, convicted, and sentenced to death.
- Smith conceded he committed the killing; his sole defense at trial was insanity.
- Evidence included testimony suggesting Smith may have known the act was wrong but was unable to control his conduct due to mental disease.
- Smith requested a jury instruction allowing acquittal if, because of mental disease, he either (a) could not distinguish right from wrong, or (b) though able to do so, acted under a non-voluntary, uncontrollable impulse that destroyed his power of self-control.
- The prosecution did not object to the requested instruction.
- The trial court refused the requested instruction and charged the jury using only a cognitive “nature and quality/right and wrong” test for insanity.
- Smith appealed, arguing the insanity instruction misstated the governing law by excluding volitional incapacity.

## Issues

1. Whether the trial court committed reversible error by instructing the jury solely on the cognitive right-and-wrong test and refusing to instruct on insanity based on an uncontrollable, disease-induced impulse.
2. Whether a defendant who understands an act is wrong may still be legally insane if mental disease deprives him of the power to choose and control his conduct.

## Decision

- The appellate court reversed the conviction and death sentence and remanded for further proceedings.
- The court held the insanity instruction was erroneous because it ignored the recognized doctrine that insanity may exist where mental disease produces an irresistible impulse.
- The court concluded the jury should have been permitted to acquit if it found that mental disease overrode Smith’s reason and judgment and deprived him of volitional control, even if he knew the act was wrong.

## Legal Principles

- In jurisdictions recognizing irresistible impulse, the insanity defense is not limited to inability to know the nature of the act or that it is wrong.
- Knowledge of right and wrong, standing alone, is not a complete test of criminal responsibility when insanity is asserted.
- A defendant may be legally insane if mental disease creates an uncontrollable impulse that overrides reason and judgment and deprives the defendant of the power to choose between right and wrong.
- A trial court commits instructional error if it forecloses the jury from considering a properly supported insanity theory grounded in volitional incapacity.

## Conclusion

The court held that the insanity standard required consideration of both cognitive incapacity and disease-driven loss of self-control; because the jury was instructed only on the right-and-wrong test, the conviction was reversed and the case remanded for a new trial with a correct insanity instruction.


Smith v. United States, 36 F.2d 548 (D.C. Cir. 1929)