The offense most people still call “adultery” in the military went through a substantial rewrite that took effect on January 1, 2019. That rewrite came out of the Military Justice Act of 2016, a sweeping reform statute that Congress passed as part of the National Defense Authorization Act for Fiscal Year 2017. The Act directed a comprehensive overhaul of the Uniform Code of Military Justice, and the President implemented the detailed changes through a revised Manual for Courts-Martial. The adultery provision was one of many enumerated offenses under Article 134 that were updated in the process.
Understanding what actually changed requires separating three things: the name of the offense, the conduct it covers, and the defenses available to an accused service member. All three moved.
From “Adultery” to “Extramarital Sexual Conduct”
Before 2019, the listed offense under Article 134 was titled “Adultery.” After the Manual for Courts-Martial was revised, the same provision became “Extramarital sexual conduct.” In the current Manual it appears as Part IV, paragraph 99. The renaming was not merely cosmetic. The old label described a narrow act, while the new label was chosen to match a broader range of conduct that the drafters wanted the provision to reach.
Article 134 itself is codified at 10 U.S.C. section 934 and is known as the general article. It punishes conduct prejudicial to good order and discipline and conduct of a nature to bring discredit upon the armed forces. Adultery, and now extramarital sexual conduct, has always been an enumerated example listed under that general article rather than a free standing statute with its own code section.
The Conduct Itself Was Broadened
Under the older version, the offense was generally understood to require sexual intercourse, defined in traditional terms between a man and a woman. That narrow definition left obvious gaps. The 2019 revision replaced the single act with a defined set of acts. The Manual now describes “extramarital conduct” to include genital to genital, oral to genital, anal to genital, and oral to anal contact, and it applies regardless of whether the participants are of the same or opposite sex.
This change closed loopholes that had drawn criticism for years. Conduct that fell outside the old definition of intercourse could now be charged, and the provision became gender neutral. The practical effect is that the universe of chargeable conduct grew even as, in other respects, the government’s path to a conviction narrowed.
The Elements the Government Must Prove
The current version of the offense requires the government to prove three elements beyond a reasonable doubt. First, that the accused wrongfully engaged in extramarital conduct with a certain person. Second, that at the time, the accused or the other person was married to someone else. Third, that under the circumstances the conduct was either to the prejudice of good order and discipline in the armed forces, of a nature to bring discredit upon the armed forces, or both.
That third element is the heart of the matter and reflects the general article. Extramarital conduct, standing alone, is not automatically a crime under the UCMJ. The government must connect the conduct to a genuine military effect. To structure that analysis, the Manual sets out a list of factors that commanders and courts weigh, found at Part IV, paragraph 99.c. These include the marital status, military rank, grade, or position of the participants, the impact on the unit, whether the conduct was open and notorious, and the effect on the parties’ military duties. The presence of these factors helps separate conduct that truly harms the service from private conduct that does not.
New and Clarified Defenses
The most significant practical change for an accused service member was the addition of a defense based on legal separation. Under the prior framework, a service member could remain exposed to an adultery charge even after living apart from a spouse for years, because only a final divorce removed marital status. The revised Manual recognizes that conduct is not punishable when the accused and the other person were legally separated, or were unmarried, at the time. Importantly, the Manual treats legal separation as something accomplished by court order rather than mere physical separation, so simply moving out is not enough.
The revision also preserved and clarified the defense of mistake of fact. If the accused held an honest and reasonable belief that he or she, and the other person, were unmarried or legally separated, that belief can defeat the knowledge element. When the accused raises some evidence of such a belief, the burden shifts to the government to disprove it beyond a reasonable doubt.
Punishment Did Not Become More Lenient
For offenses under the current Manual, the maximum punishment for extramarital sexual conduct remains a dishonorable discharge, forfeiture of all pay and allowances, and confinement for one year. The reform changed the definition and the available defenses, but it did not reduce the ceiling on punishment. Sentencing procedures themselves were later affected by additional reforms that introduced standardized sentencing for offenses committed on or after December 27, 2023, but the underlying maximum for this offense has stayed the same.
Why the Change Matters
Taken together, the 2019 revision modernized a provision that had been criticized as both too narrow in the acts it described and too broad in the relationships it could touch. It expanded the kinds of sexual conduct that qualify, made the provision gender neutral, and at the same time gave service members a meaningful legal separation defense and a clarified mistake of fact defense. For anyone evaluating a current case, the date of the alleged conduct matters: conduct before January 1, 2019 is measured against the old “Adultery” definition, while conduct on or after that date is measured against the “Extramarital sexual conduct” provision in paragraph 99 of the current Manual. Anyone facing such an allegation should consult a qualified military defense attorney who can apply the version of the law that governs the specific dates at issue.
Disclaimer
This article is provided strictly for general educational and informational purposes. It is intended to explain how the Uniform Code of Military Justice (UCMJ), the Rules for Courts-Martial, the Military Rules of Evidence, and related military administrative processes work as a matter of public legal education. It does not constitute legal advice, a legal opinion, or a recommendation about any particular case, and it is not a substitute for advice from a qualified military defense attorney who can evaluate the specific facts and command, service, and jurisdictional circumstances involved.
Reading this article, or contacting any website on which it appears, does not create an attorney-client relationship between the reader and any law firm, attorney, or author. Every court-martial, nonjudicial punishment action, administrative separation, and security-clearance matter turns on its own facts, the charged articles, the convening authority, the service branch, and the evidence, and outcomes vary widely from one case to another.
Military law also changes over time. The Military Justice Act of 2016 (effective January 1, 2019) and subsequent National Defense Authorization Acts renumbered and rewrote many punitive articles, revised the Article 32 preliminary hearing, and altered sentencing, clemency, and appellate procedures. Statutes, regulations, executive orders, the Manual for Courts-Martial, and decisions of the service Courts of Criminal Appeals and the Court of Appeals for the Armed Forces may have been amended, superseded, or reinterpreted after this article was written, and article numbers or procedures cited here may have changed.
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