How Does the Military Justice System Intersect with International Humanitarian Law and the Law of Armed Conflict?
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Under the Manual’s charging guidance, U.S. service members who violate the law of armed conflict are charged with the underlying UCMJ offense, such as murder, assault, maltreatment, or dereliction of duty, rather than with a “war crime” as such: the Manual says that “Ordinarily persons subject to the UCMJ should be charged with a specific violation of the UCMJ rather than a violation of the law of war” (R.C.M. 307, Discussion). General courts-martial also have jurisdiction to try “any person who by the law of war is subject to trial by a military tribunal” (Article 18(a)), and the federal War Crimes Act separately makes war crimes by or against members of the U.S. armed forces federal offenses (18 U.S.C. § 2441).
Three legal routes
| Route | Who | What is charged | Forum |
|---|---|---|---|
| UCMJ punitive articles | Persons subject to the UCMJ | The specific offense, such as Articles 77, 92, 93, 118, 128 | Court-martial |
| Law of war under Article 18 | "any person who by the law of war is subject to trial by a military tribunal" | "Violation of the Law of War", or the law of an occupied territory (R.C.M. 201(f)(1)(B); R.C.M. 307, Discussion) | General court-martial |
| War Crimes Act | Offenses inside the United States, or anywhere if the victim or offender is a U.S. national, lawful permanent resident, or member of the U.S. armed forces, or the offender is present in the United States | War crime as defined in § 2441(c) | Federal court |
Military commissions under 10 U.S.C. chapter 47A are a separate system for alien unprivileged enemy belligerents; see military commissions versus courts-martial.
Charging through the UCMJ
Law-of-war violations by U.S. personnel map onto existing articles:
- a deliberate killing of a protected person can be murder under Article 118;
- abuse of a detainee can be assault under Article 128 or cruelty and maltreatment of a person subject to one’s orders under Article 93;
- failure to carry out a duty, including a duty to prevent or report violations, can be dereliction under Article 92(3), “is derelict in the performance of his duties”;
- conduct not covered by a specific article may be charged under Article 134, within the limits of the preemption doctrine.
The law-of-war context affects the facts and the gravity of the case, but the government must prove the elements of the article charged.
Liability of commanders
The UCMJ has no separate command-responsibility article. A commander who “commits an offense punishable by this chapter, or aids, abets, counsels, commands, or procures its commission”, or “causes an act to be done which if directly performed by him would be punishable”, is a principal (Article 77). A commander who fails in a duty to supervise, prevent, or report may be charged with dereliction under Article 92(3). Conspiracy under Article 81 is another route where there was an agreement.
The defense of obedience to orders
“It is a defense to any offense that the accused was acting pursuant to orders unless the accused knew the orders to be unlawful or a person of ordinary sense and understanding would have known the orders to be unlawful” (R.C.M. 916(d)). The Discussion adds that the lawfulness of an order is ordinarily decided by the military judge. Under this rule, an order whose unlawfulness a person of ordinary sense and understanding would recognize, such as an order to kill civilians or prisoners under one’s control, provides no defense to the subordinate who carries it out.
Law-of-war jurisdiction of general courts-martial
“General courts-martial may try any person who by the law of war is subject to trial by military tribunal for any crime or offense against” the law of war, or the law of a territory occupied as an incident of war when local civil authority is superseded, and may adjudge any punishment the law of war permits (R.C.M. 201(f)(1)(B); Article 18(a)). The Discussion notes that international conventions, such as Article 68 of the Geneva Convention Relative to the Protection of Civilian Persons in Time of War, limit the punishments military tribunals may impose under this authority.
The War Crimes Act
Section 2441 punishes, “whether inside or outside the United States,” a war crime committed in the circumstances listed in subsection (b), with imprisonment up to life and death if the victim dies (18 U.S.C. § 2441(a)). A “war crime” includes conduct defined as a grave breach of the 1949 Geneva Conventions or a protocol the United States has joined, conduct prohibited by Articles 23, 25, 27, or 28 of the Annex to Hague Convention IV of 1907, grave breaches of common Article 3 in non-international armed conflicts, and certain violations of the amended Protocol II on mines and booby-traps (§ 2441(c)). A 2023 amendment (Pub. L. 117-351) rewrote the jurisdiction subsection to reach offenders present in the United States regardless of nationality.
Where these cases arise
Deployed operations raise their own jurisdiction and evidence issues, covered in military justice in deployed and combat environments. Leading decisions on court-martial jurisdiction and the military commissions are discussed in the landmark cases that shaped military law.
A detainee beating, three charges (hypothetical)
A squad leader orders subordinates to beat a detainee, and a platoon leader learns of it and does nothing. The squad leader may be charged as a principal to assault under Articles 77 and 128, and with maltreatment under Article 93; the subordinates who carried out the beating cannot rely on R.C.M. 916(d) if a person of ordinary sense and understanding would have known the order was unlawful. The platoon leader may be charged with dereliction under Article 92(3) if the government proves a duty to act and a failure to perform it.
Sources
- 10 U.S.C. § 818, Article 18 (Cornell LII)
- 10 U.S.C. § 877, Article 77, Principals (Cornell LII)
- 10 U.S.C. § 892, Article 92, Failure to obey order or regulation (Cornell LII)
- 18 U.S.C. § 2441, War crimes, with 2023 amendment note (Cornell LII)
- Manual for Courts-Martial, United States (2024 ed.), R.C.M. 201(f)(1)(B), 307, 916(d); Part IV, ¶91
This article is general information about military law, not legal advice for any individual case.