WASHINGTON - More than one-third of U.S. soldiers in Iraq surveyed by the Army said they believed torture should be allowed if it helped gather important information about insurgents, the Pentagon disclosed yesterday. Four in 10 said they approved of such illegal abuse if it would save the life of a fellow soldier.

In addition, about two-thirds of Marines and half the Army troops surveyed said they would not report a team member for mistreating a civilian or for destroying civilian property unnecessarily. "Less than half of Soldiers and Marines believed that non-combatants should be treated with dignity and respect," the Army report stated.

About 10 percent of the 1,767 troops in the official survey - conducted in Iraq last fall - reported that they had mistreated civilians in Iraq, such as kicking them or needlessly damaging their possessions.

"They looked under every rock, and what they found was not always easy to look at," S. Ward Casscells, the assistant secretary of defense for health affairs, said of Army researchers who conducted the survey. The report noted that the troops' statements were at odds with the "soldier's rules" promulgated by the Army, which forbid the torture of enemy prisoners and state that civilians must be treated humanely.

Maj. Gen. Gale Pollock, the acting Army surgeon general, cast the report as positive news. "What it speaks to is the leadership that the military is providing, because they're not acting on those thoughts," she said. "They're not torturing the people."

Human-rights activists said the report lent support to their view that the abuse of Iraqi civilians by U.S. military personnel was not isolated to some bad apples at Abu Ghraib and a few other detention facilities. "These are distressing results," said Steven Shapiro, national legal director for the American Civil Liberties Union. "They highlight a failure to adequately train and supervise our soldiers."

The Army has surveyed mental-health issues in Iraq three times before, but this was the first time that Marines were included and that ethical questions were posed.

The study also found that the more often soldiers were deployed, the longer they were deployed each time, and the less time they spent at home, the more likely they were to suffer mental-health problems such as combat trauma, anxiety and depression. That result is particularly notable given that the Pentagon has sent soldiers and Marines to Iraq multiple times and recently extended the tours of thousands of soldiers from 12 to 15 months.

The authors of the Army document argued that the strains placed on troops in Iraq were in some ways more severe than those borne by the combat forces of World War II.

"A considerable number of Soldiers and Marines are conducting combat operations every day of the week, 10-12 hours per day, seven days a week for months on end," wrote Col. Carl Castro and Maj. Dennis McGurk, who are psychologists. "At no time in our military history have Soldiers or Marines been required to serve on the front line in any war for a period of 6-7 months."

And although U.S. casualties in Iraq are far lower than in the Vietnam War, for example, military experts say Iraq can be a more stressful environment. In Vietnam, there were rear areas that were considered safe, but in Iraq, there are no truly secure areas outside big bases. "The front in Iraq is anyplace not on a base camp" or a forward operating base, the report noted.

The authors recommended that soldiers be given breathers during combat tours and also intervals of 18 to 36 months between such tours, substantially longer than they are allowed now.

Overall, 20 percent of the soldiers surveyed and 15 percent of the Marines appeared to suffer from depression, anxiety or stress, the Army reported. That was in keeping with findings of past surveys, as was the conclusion that more than 40 percent of soldiers reported low morale in their units.

Strains on military families also are intensifying. About 20 percent of soldiers said they were planning a divorce or separation, up from 15 percent in the previous year's survey. Marital problems seem to grow with the length of a deployment, the survey found.

Pollock said that, in response to the report completed in November, the Army already has altered training.