UCMJ Article 77: Principals

Article 77 does not create a crime. It makes anyone who aids, abets, counsels, commands, or procures an offense, or causes it through another, guilty of that offense and punishable to the same extent as the person who committed it. A charge is brought under the underlying article, such as larceny under Article 121, with Article 77 supplying the theory of liability.

Who § 877 makes a principal

Under 10 U.S.C. § 877, a person punishable under the UCMJ is a principal who “commits an offense punishable by this chapter, or aids, abets, counsels, commands, or procures its commission,” or who “causes an act to be done which if directly performed by him would be punishable by this chapter.”

The Manual for Courts-Martial (2024 ed.), Part IV, ¶ 1.c(1), explains that the article erases the common-law categories of principal in the first degree, principal in the second degree, and accessory before the fact. All are principals. An accessory after the fact remains separate, under Article 78, with a lower maximum.

Perpetrators and other parties

Perpetrator. A perpetrator commits the offense by the perpetrator’s own hand, or by knowingly or intentionally setting in motion an innocent agent. The Manual’s example: a person who hides drugs in a car and has an unaware driver take it onto an installation is guilty of wrongful introduction, and the driver is guilty of nothing (¶ 1.c(2)(a)).

Other parties. Anyone else is guilty only if that person assisted, encouraged, advised, instigated, counseled, commanded, or procured the offense, and shared in the criminal purpose or design (¶ 1.c(2)(b)). Unknowing help is not a crime.

When doing nothing makes a person a principal

The Manual answers this directly: “If a person (for example, a security guard) has a duty to interfere in the commission of an offense, but does not interfere, that person is a party to the crime if such a noninterference is intended to and does operate as an aid or encouragement to the actual perpetrator” (¶ 1.c(2)(b)). A person with no such duty who merely knows of a planned crime and stays out of it is not a principal; a person with the duty who stands aside to help it along can be.

Presence works the same way in reverse. It is not necessary: someone who hands over a pistol knowing and intending that it be used in an assault is guilty of the assault without being there. And it is not sufficient: “Mere presence at the scene of a crime does not make one a principal unless the requirements of subparagraph 1.b.(2)(a) or (b) have been met” (¶ 1.c(3)).

Different intent, different offense

Where the offense requires a specific intent or state of mind, each party is judged by that party’s own (¶ 1.c(4)). The Manual’s examples cut both ways:

• A perpetrator who kills in the heat of sudden passion may be guilty of manslaughter, while a calm party who hands over the weapon and urges the killing is guilty of murder.
• A party who helps assault someone, not knowing the victim is an officer, is guilty only of assault, while the perpetrator who knew is guilty of assault on an officer.

Liability for other crimes, and withdrawal

A principal may be convicted of other crimes committed by another principal “if such crimes are likely to result as a natural and probable consequence of the criminal venture or design”; a party to a burglary in which the perpetrator kills an occupant can be guilty of murder (¶ 1.c(5)). A principal can be convicted even if the perpetrator is never identified, prosecuted, or is acquitted (¶ 1.c(6)).

Withdrawal avoids liability for offenses committed afterward only if it meets three conditions (¶ 1.c(7)):

1. It occurs before the offense is committed.
2. The assistance, encouragement, or other contribution is effectively countermanded or negated.
3. It is clearly communicated to the would-be perpetrators, or to law enforcement, in time for the plan to be abandoned or the offense prevented.

The same exposure as the person who did it

Article 77 has no maximum of its own. A principal “may be punished to the same extent” as the person who directly commits the offense (¶ 1.c(1)), so the ceiling comes from the underlying article: an aider and abettor of robbery faces the robbery maximum. Agreement plus an overt act is separately punishable as conspiracy under Article 81, and both can be charged alongside the completed offense.

Sources

• 10 U.S.C. § 877, Article 77, Principals (Cornell LII)
• Manual for Courts-Martial, United States (2024 ed.), Part IV, ¶ 1

General information about military law, not legal advice for any individual case.