CASES PUT MILITARY AFFAIRS IN SPOTLIGHT; ARMED FORCES LAX IN ADULTERY POLICY.

Byline: Ian Fisher The New York Times

The big man with brush-bristle hair - the telltale trait of a soldier - seemed neither ashamed nor especially proud of himself as he emerged from a private room of the Casa Colorada here.

He is married. But he just spent $40 for five minutes of sex with a woman in this brothel across the border from El Paso, Texas, decorated with great drama in red, from the walls to the lamps to the felt of the pool table, where two unhired prostitutes shot a quiet game.

``It shouldn't be,'' said the soldier, who is 33 and stationed away from his family at the Fort Bliss Army base in El Paso. ``But everyone is human. It's going to happen.''

The soldier summed up succinctly the confusion in the military over the issue of adultery - which has emerged as the latest question of sexual misconduct to snarl the armed forces.

On one hand, the military decided long ago that adultery was a threat to discipline, and the act is illegal under military law, punishable by reprimand, dismissal and, in rare cases, prison.

But it is common and commonly overlooked, even if it is not nearly as overt as it was just a few decades ago. With people away from their families for long stretches of time, adultery has been, if not condoned, often tolerated.

For years, boxes of condoms were left on the quarterdecks for sailors, single or not, going ashore. Soldiers long maintained live-in girlfriends abroad in places like South Korea. To this day, houses of prostitution flourish around foreign bases and ports of call, and it is no secret that many of the military customers are married.

The offense of adultery also encompasses a vast range of encounters that are routine to civilian life, from a one-night stand with a co-worker to a loving, long-term relationship outside of a troubled marriage. So, regardless of the circumstances, an informal working rule on adultery has developed, implied in military law and expressed in interviews with service members in El Paso and Juarez: Do what you want, but don't do it blatantly and don't get caught.

``They are really not concerned about it unless something happens,'' said a married, 29-year-old specialist from Brooklyn, N.Y., on a recent night on the town in Juarez. ``If nothing happens,'' he added, meaning that an affair remains discreet, ``they don't give a heck.''

It is a standard with a shifting bottom line, and experts and critics of the military say that is what has brought the armed forces to its current struggle over adultery after years of public battles with other sexual conduct, from homosexual behavior to sexual harassment and rape.

In a high-profile case that has embarrassed the Air Force, 1st Lt. Kelly Flinn, a single woman and the first female pilot of a B-52 bomber, is scheduled to be court-martialed Tuesday for affairs she had with a married man and an enlisted soldier. Last week, the Army's top enlisted soldier, Sgt. Maj. Gene C. McKinney, was charged with adultery among other offenses relating to allegations that he sexually harassed four servicewomen.

And casting a tragic shadow over the debate is the case of a 41-year-old Air Force lieutenant colonel, Karen Tew, who committed suicide in March after pleading guilty to having an affair with an enlisted man. A year shy of retirement, she had been dismissed from the service.

For the military, the issue of adultery is spelled out plainly as Article 134 of the Uniform Code of Military Justice. There are three elements to the crime, two of which seem perfectly clear: that a soldier had sex and that one of the parties was married to someone else.

The third element is more subjective: that the conduct harmed ``good order and discipline'' and was ``of a nature to bring discredit upon the armed forces.'' That condition, according to a Pentagon legal official, is a crucial part of the law, even though he acknowledged that it creates the impression that prosecution is selective.

``It's dangerous,'' said the official, who spoke on the condition of anonymity. ``You always leave yourself open to the kind of criticism the services are getting: Well, you treated this person differently from that person. The problem is all those circumstances that feed into individual judgment don't always get played out in the media or anecdotal accounts.''

For example, the military has a strong interest in disciplining cases of adultery within a company because its cohesion is considered critical to life and death. It is also concerned with disciplining officers or ranking enlisted soldiers who must command the respect of their troops. And in general, military officials say, an adultery case has proceeded only when it involved ``egregious'' conduct and was specifically brought to a commander's attention, often by a wronged spouse.