It was enough to sink the career of Adm. Ralph Tindal and to drive 12th Air Force Lt. Gen. Thomas R. Griffith into retirement.
It is among the raft of charges brought against the defendants at the Army's Aberdeen Proving Ground, where sergeants are accused of infractions from sexual harassment to sodomy and rape.
Now, allegations of adultery--in combination with other charges--threaten to dishonor Lt. Kelly Flinn, who made history as the nation's first woman B-52 pilot.
At a time when civilians seem to take a casual view of the breach of marriage vows--it is rarely prosecuted and is not even on the books in some states--the Pentagon is eyeing adultery as a rising threat for two major reasons:
There are more women than ever in the armed forces today, and thus the temptations are more numerous. At the same time, the military is striving to be more family- oriented, and adultery poses a greater threat to cohesion.
"The risk of this has increased, and I think so has the attention they're paying to it," says David Segal, a military sociologist at the University of Maryland.
Military law defines adultery as sex outside of marriage in circumstances that may prejudice "good order and discipline in the armed forces." The last phrase is key: It may explain why the severest punishments tend to be meted out to those carrying on with subordinates, those who have the poor judgment to attract a lot of public notice, or hold very senior posts.
If a commanding officer learns that two soldiers are quietly conducting an adulterous affair, the officer may take them aside for a simple chewing-out.
But the offense is likely to be treated far more seriously if the adultery involves sex between an officer and a subordinate, an officer and the spouse of subordinate, or a drill sergeant and a recruit he or she supervises. In each of those cases, the relationship is more dangerous because it may sow resentment among subordinates in the chain of command, or involve coercion by a superior.
The commander is likely to move forcefully, too, if the affair is stirring comment--"even whispers from the outside. That's going to be pretty devastating to the organization," said one military lawyer.
Commanding officers have various options. They can send the subordinate for counseling, issue a warning or a letter of reprimand, or begin an administrative proceeding that can lead to a fine or even confinement.
The most serious cases involve a general court-martial and carry a maximum penalty of one year's imprisonment, forfeiture of a year's pay, and dishonorable discharge for enlisted personnel and dismissal for officers.
Frequently, when the military gets around to filing a combination of charges, it means "the military feels this person has crossed the line--they've just had enough," said Eugene R. Fiddell, a military law specialist in Washington.
That may have been the case with Flinn.
Last month, Flinn, a 1993 Air Force Academy graduate, was charged--along with disobeying a superior's order, lying and fraternization--with having an improper relationship between an officer and an enlisted man.
Authorities at the 23rd Bomb Squadron, in Minot, N.D., said she was having sex with an enlisted airman, and also had carried on an affair with the civilian husband of a junior enlisted woman.
The military also said she had disobeyed a superior's earlier order to stay at least 100 feet away from one of the men she was seeing as well as his home, and that she had lied to investigators. (Flinn's case now rests with Air Force authorities, who could dismiss the case, order a trial or seek other actions.)
Adultery has always been listed by the military as an offense, but prosecution has been inconsistent.
During the Civil War, for example, the Union Army's officer corps didn't bring soldiers up on charges, although officers, who considered themselves an elite corps, considered it a grave offense when the infraction was committed by one of their own.
During this century, violations have often been overlooked, including those of senior officers. According to some historians, Gen. Dwight D. Eisenhower, when he was Supreme Allied Commander in World War II, carried on a wartime affair with an Irish-born military aide, Kay Summersby.
And in some modern conflicts, commanders have indirectly encouraged adultery by helping make available the prostitutes they believed would help maintain morale.
But since the Vietnam War, the military's attitude has shifted as the services sought to tighten up their moral code, which had become permissive during the days of an unpopular draft.
These days, the military services are promulgating new codes of honor for service members to cleanse recruits of the lax habits of the outside. Adultery is on the proscribed list.
To be sure, the military brings relatively few cases to a court-martial, and usually resorts to this final step only when the accused has committed other infractions. Many adulterous affairs go on unknown to the authorities because, as one former Army officer put it, "no one here is going to organize a bedroom police."
But commanding officers do care, and use many means short of courts-martial to halt a practice they believe strikes at the heart of the order that is key to military life.
And when it is the top officers themselves who are involved in adulterous affairs, punishment can be severe because adultery by them is thought to pose a special threat to morale.
Rear Adm. Ralph Tindal was Deputy Supreme Allied Commander Atlantic of NATO when he was caught in an adulterous affair with a junior enlisted woman two years ago.
In an administrative hearing, he was found guilty of adultery, fraternization and sexual harassment, because the woman claimed she wanted to end the affair. Tindal was relieved of command, confined to quarters for 30 days, reduced in rank and pay, and forced to retire.
Lt. Gen. Griffith, a 28-year veteran who commanded 43,000 Air Force personnel in the 12th Air Force, was forced into retirement when it came to light that he had an affair with a woman he had met at a management conference.
Officers "are held to a higher standard," a Pentagon spokesman said in September 1995, when the punishment was announced.
In the Air Force, the number of adultery cases referred to trial has ranged between 11 and 22 each year this decade. But the numbers are deceiving, because they don't reflect the many more that are handled behind closed doors in administrative proceedings.
"You can ask whether this should be criminalized at all," says David Brahms, a retired Marine brigadier general and expert on military law. "I could make a case that we should get rid of a lot of these like offenses and handle them as employment matters."
Overall, however, the use of the charge by the military seems to face little challenge.
"The military's take is that being in the armed forces simply requires a higher level of probity," says lawyer Fiddell. "And that isn't likely to change."