WASHINGTON – The blame for abuses at Iraq’s Abu Ghraib prison lies mainly with the American soldiers who ran the notorious jail, but senior commanders and top-level Pentagon officials including Defense Secretary Rumsfeld can be faulted for failed leadership and oversight, an independent commission said yesterday.

“There was chaos at Abu Ghraib,” said James Schlesinger, who headed the four-person commission appointed by Mr. Rumsfeld.

The report described the abuse as “acts of brutality and purposeless sadism,” and said – as have others who reviewed the case – that the soldiers involved were not acting on approved orders or policies.

On the other hand, the report contradicts the Bush administration’s assertion that the problem was limited to a few soldiers acting on their own. So far, seven military police soldiers have faced criminal charges; two dozen or more military intelligence soldiers may also be charged, but it appears increasingly unlikely that top-level commanders will be disciplined.

No senior officials deserve to be punished, the Schlesinger commission members told a Pentagon news conference after briefing Mr. Rumsfeld. They said they believe the Pentagon is on a path to remedying the underlying causes of the abuse.

Mr. Schlesinger said soldiers who stacked naked Iraqi prisoners in pyramids, forced them into positions of sexual humiliation, and confronted them with snarling guard dogs were renegades.

“It was a kind of ‘Animal House’ on the night shift,” he said. Mr. Schlesinger was a secretary of defense for the Nixon and Ford administrations.

The Schlesinger commission was not asked to assign legal culpability; that is being done in Army investigations, including one, known as the Fay report, scheduled to be made public today.

The Schlesinger panel, which reviewed the Fay report and other related investigations, said disciplinary action “may be forthcoming” against Brigadier General Janis Karpinski, who commanded the 800th Military Police Brigade at Abu Ghraib; and Colonel Thomas Pappas, commander of the 205th Military Intelligence Brigade, which was assigned to Abu Ghraib last year.

Brigadier General Karpinski contends she was not alerted to abuses at Abu Ghraib until they were brought to the attention of Lieutenant General Ricardo Sanchez, the top American commander in Iraq, in January 2004.

The Schlesinger report aims significant blame at Lieutenant General Sanchez, saying that while he was understandably focused on fighting a mounting Iraqi insurgency at the time of the abuses, he should have ensured that his staff dealt with Abu Ghraib’s command and resource problems.

“Commanders are responsible for all their units do or fail to do, and should be held accountable for their action or inaction,” the report said.

The report is one of several that have examined various aspects of the abuse scandal, which rocked the Bush administration and triggered calls by some in Congress for Mr. Rumsfeld to resign. Its findings are similar to that of other reviews, although it is the first to point blame at Mr. Rumsfeld and General Richard Myers, chairman of the Joint Chiefs of Staff.

“There is no evidence of a policy of abuse promulgated by senior officials or military authorities,” the report said. “Still, the abuses were not just the failure of some individuals to follow known standards, and they are more than the failure of a few leaders to enforce proper discipline. There is both institutional and personal responsibility at higher levels.”

Senior leaders did not establish clear guidelines on permissible techniques for interrogating various categories of prisoners held at Abu Ghraib and elsewhere in Iraq, the report said.

Mr. Rumsfeld might have avoided confusion over interrogation policy in the months after Baghdad fell in April 2003 if he had a wider range of legal opinions and a more robust internal debate over detainee policies and operations in 2002, before the war started, the report said.

Also yesterday, the American military judge hearing charges of prisoner abuse at Abu Ghraib rejected a request for Mr. Rumsfeld to submit to an interview, but said he would reconsider if the defense could show a Rumsfeld link to the case.

Judge Colonel James Pohl also suggested he would compel top military intelligence commanders to testify unless prosecutors move forward with criminal charges against them by September 17. So far, the commanders have refused to testify on grounds they could incriminate themselves.

The request to interview Mr. Rumsfeld and his deputy, Stephen Cambone, came from a lawyer for defendant Specialist Javal Davis at a pretrial hearing. While the judge rejected it, he said it could be brought back if the defense can fill in some gaps.