## Facts

- Karl Heynen, a German noncommissioned officer during World War I, supervised a prisoner-of-war labor detachment in Westphalia that included British prisoners.
- Heynen was responsible for guarding and directing POW labor, including taking British POWs to work in a mine; some resisted the work assignments.
- Communication problems arose; Heynen used a POW as an interpreter and reacted with insults and verbal abuse when dissatisfied with translations.
- Heynen repeatedly used physical violence against POWs, including striking one prisoner in the face and beating others, including prisoners claiming illness.
- Complaints and disturbances led to Heynen’s removal from the post; after the war he was prosecuted as part of the Leipzig war-crimes proceedings.
- The prosecution also alleged Heynen ordered beatings of POWs who resisted work, but the court treated this allegation separately based on the evidentiary record.

## Issues

1. Whether a camp overseer’s assaults and degrading treatment of prisoners of war constituted a punishable offense under domestic criminal law as informed by the laws and customs of war governing POW treatment.
2. Whether the evidence was sufficient to prove the more serious allegation that Heynen issued a general order to beat POWs who resisted work.
3. Whether wartime conditions, lack of training, lower rank, or acting under orders excused or mitigated criminal responsibility for POW mistreatment.

## Decision

- The Reichsgericht convicted Heynen for ill-treatment of British prisoners of war based on multiple acts characterized as extremely rough brutality.
- The court sentenced Heynen to ten months’ imprisonment.
- The court acquitted Heynen on the allegation that he ordered beatings of POWs who refused to work, finding the proof insufficient to establish that charge with the required certainty.
- The court treated lack of training and wartime pressures as relevant to punishment, but not as a defense to deliberate brutality.

## Legal Principles

- Individuals exercising authority over prisoners of war may be criminally liable for unnecessary violence and degrading treatment exceeding any permissible disciplinary power.
- Domestic criminal provisions on bodily injury and abuse of authority can apply to POW mistreatment, with treaty-based and customary rules of war informing what treatment is unlawful.
- Conviction on alleged command-level misconduct (such as issuing a general order to beat resisters) requires strict proof; uncertainty in witness testimony warrants acquittal on that distinct charge.
- Stressful conditions, lower rank, and imperfect preparation may mitigate sentencing but do not excuse intentional, gratuitous violence against protected persons.

## Conclusion

The court imposed criminal punishment for direct brutal mistreatment of prisoners of war while refusing to convict on a broader “order to beat” accusation absent sufficient proof, reflecting an approach that linked domestic criminal liability to international POW-protection norms but maintained a demanding evidentiary standard for additional command-related allegations.


In re Karl Heynen, 16 Am. J. Int’l L. 674 (1922)