## Facts

- A woman in Tochigi Prefecture was subjected to repeated sexual assault by her father beginning in adolescence and continuing for about 15 years; the abuse resulted in pregnancies and children.
- As an adult, she sought to marry another man; her father responded by confining her for days, abusing her, and threatening to kill her children.
- On October 5, 1968, after the father, intoxicated, attacked her again, she resisted, overpowered him, and killed him by strangulation.
- The prosecution indicted her under Criminal Code Article 200, which mandated death or life imprisonment for killing a lineal ascendant.
- The district court held Article 200 unconstitutional and acquitted; the high court upheld Article 200’s constitutionality, rejected complete self-defense, and imposed a mitigated prison term of three years and six months.
- On final appeal, the Supreme Court (Grand Bench) reviewed the constitutionality of Article 200’s penalty scheme and the resulting sentence.

## Issues

1. Whether Criminal Code Article 200’s categorical, harsher punishment for killing a lineal ascendant violates the constitutional guarantee of equality under the law, including the ban on discrimination based on “family origin.”
2. If Article 200 cannot be constitutionally applied, whether the offense must be sentenced under ordinary homicide (Article 199) and what sentencing consequences follow in light of severe mitigating circumstances.

## Decision

- The Supreme Court held that Article 200’s mandatory, substantially harsher penalty for parricide violated constitutional equality guarantees.
- The Court treated the offense as ordinary homicide under Article 199 rather than parricide under Article 200.
- Reassessing punishment under Article 199 and considering the prolonged abuse, confinement, and threats, the Court imposed a prison sentence with suspended execution, allowing the defendant to remain at liberty absent reoffending.
- The ruling effectively invalidated Article 200 and precipitated its later legislative repeal.

## Legal Principles

- A criminal punishment scheme that categorically aggravates homicide penalties solely due to lineal family status can violate constitutional equality guarantees where the classification reflects impermissible discrimination tied to family hierarchy.
- Legislative discretion to differentiate crimes and penalties has constitutional limits when the differentiation produces arbitrary, status-based discrimination.
- Mandatory penalties that prevent meaningful consideration of extreme mitigating circumstances may be constitutionally unacceptable where they foreclose individualized sentencing and yield gross disproportionality in application.
- When a special aggravated-offense provision is unconstitutional, courts may apply the general offense provision to determine conviction and sentence.

## Conclusion

The Supreme Court invalidated Japan’s mandatory parricide punishment as inconsistent with constitutional equality, resentenced the defendant under ordinary homicide to a suspended term, and set the course for repeal of the parricide provision.


Prosecutor v. Aizawa, Hanrei Jihō (No. 697) 3 (S. Ct. Japan 1973)