A lack of foresight and oversight led to the abuse of prisoners at Iraq's Abu Ghraib (search) prison at the hands of U.S. military police and intelligence interrogators last year, according to an independent report released Tuesday.

The report — dubbed the "Schlesinger report" after lead investigator and former Defense Secretary James Schlesinger (search) — said the direct responsibility lay with soldiers and commanders in the field rather than in Washington.

"There was chaos at Abu Ghraib," Schlesinger said during an afternoon press conference releasing the Defense Department commissioned report, and "sadism on the night shift."

"There was direct responsibility for those activities on the part of the commanders on the scene up to the brigade level, because they did not adequately supervise what was going on at Abu Ghraib," Schlesinger continued. "There was indirect responsibility at higher levels, in that the weaknesses at Abu Ghraib were well-known and that corrective action could have been taken and should have been taken."

He said Defense Secretary Donald Rumsfeld's office could be faulted for inadequate supervision, but he strongly objected to the suggestion that Rumsfeld should step down from his post.

"His resignation would be a boon to all of America's enemies," Schlesinger said.

The report also blames the military's Chairman of the Joint Chiefs of Staff Richard Myers (search) and Lt. Gen. Ricardo S. Sanchez (search), then the top U.S. commander in Iraq, for inadequately supervising interrogation techniques and other policies at several prisons in Cuba, Afghanistan and Iraq. But Schlesinger said his group was not looking for those officials to be reprimanded or to resign.

"We believe Lt. Gen. Sanchez should have taken stronger action in November when he realized the extent of the leadership problems at Abu Ghraib," the report said. It concluded that he "failed to ensure proper staff oversight" of detention and interrogation operations.

However, the findings conclude first and foremost, that much of the detainee/interrogation procedures put to use in Iraq, Afghanistan and at Guantanamo Bay, Cuba, were accomplished according to longstanding rules, and as such, yielded vital, timely pieces of intelligence that were put to immediate use.

But in most cases, the abuse was not carried out with the purpose of achieving intelligence from prisoners, Schlesinger said.

"There were freelance activities on the part of the nightshift at Abu Ghraib," he said. "It was a kind of 'Animal House' on the night shift."

On Abu Ghraib, specifically, the report says: "The pictured abuses, unacceptable even in wartime, were not part of authorized interrogations nor were they even directed at intelligence targets. They represent deviant behavior and a failure of military leadership and discipline. However, we do know that some of the egregious abuses at Abu Ghraib which were not photographed did occur during interrogation sessions and that abuses during interrogation sessions occurred elsewhere."

The abuse was not approved, the report concluded, and no evidence suggests a policy of abuse promulgated by senior officials or military authorities, although there is both institutional and personal responsibility at higher levels.

Rumsfeld issued a statement saying, "we look forward to reviewing their analysis and recommendations in detail" and reiterated the Defense Department's commitment to make "appropriate changes" as necessary.

"We have said from the beginning that we would see that these incidents were fully investigated, make findings, make the appropriate corrections, and make them public," Rumsfeld said, promising to make future reports public, as well.

Understaffed and Under Attack

The report notes that military police units were undermanned, underequipped and poorly trained. The ratio of military police to inmates was roughly one for every 75 versus the roughly one-to-one ratio at Guantanamo Bay.

"Abu Ghraib was seriously overcrowded, underresourced and under continual attack," according to the report.

The report notes there was discussion of using some interrogation techniques that proved effective at Guantanamo Bay but a legal problem arose in that those detainees aren't protected by the Geneva Conventions as the Iraqi prisoners are.

"It is important to note that the techniques effective under carefully controlled conditions at Guantanamo became far more problematic when they migrated and were not adequately safeguarded," the report states.

One of the things that worked at Guantanamo Bay but not Abu Ghraib, for example, was a procedure in which military police are used to "soften" detainees prior to interrogation. Military police units aren't routinely trained to take on such tasks and the task proved too much for the 90 police at the prison. The result was conflict between the MPs and military intelligence operatives.

"...Compounding these problems was the inadequacy of leadership, oversight and support needed in the face of such difficulties," the report states.

The 800th Military Police Brigade, the unit whose members allegedly participated in the acts of abuse, had its detention training cancelled prior to its deployment. The report says its deployment was "chaotic."

"Equipment and troops regularly arrived out of planned sequence and rarely together. Improvisation was the order of the day," the report states. "While some units overcame these difficulties, the 800th was among the lowest in priority and did not have the capability to overcome the shortfalls it confronted."

More police personnel should have been dispatched to Abu Ghraib, the report contends, and the commanders of those who were already there -- most specifically Brig. Gen Janis Karpinski, commander of the 800th Military Police Brigade at Abu Ghraib who was suspended in May -- bore direct responsibility for the lack of discipline.

Besides Schlesinger, the other three members of the panel are: former Rep. Tillie Fowler, R-Fla., former Defense Secretary Harold Brown and retired Air Force Gen. Charles Horner.

Democrats wasted no time blasting the Bush administration for aspects of the Schlesinger report.

"The reports point out that the conditions that fostered the abusive conduct resulted from the combination of an insufficient response by the Bush administration to reports of abuse at Abu Ghraib, and the failure by leaders in Iraq to adequately supervise activities at the prison," said House Democratic leader Nancy Pelosi.

"The damage to the international standing of the United States produced by the abuses at Abu Ghraib and elsewhere can not be undone until all of those responsible are held accountable," added the California lawmaker, blaming Republicans for not conducting thorough investigations of the incidents.

Added Rep. Jane Harman, the ranking Democrat on the House Intelligence Committee: "How many more reports will it take for the President to step up, admit mistakes, and fix the problems that have occurred on his watch?"

The Fay Report

The Fay report is expected to expand the circle of people considered responsible for abuse beyond the seven military police soldiers already facing charges and will focus on the role of military intelligence soldiers at the prison. The report, expected to be released Wednesday, also singles out Sanchez as party to blame.

The list will grow to include more than a dozen others, including low-ranking soldiers, civilian contractors and medics, the Post reported. The newspaper also said the Fay report criticizes military leadership, from the prison and up through the highest levels of the U.S. chain of command in Iraq at the time.

The U.S. military judge hearing the Abu Ghraib abuse case in Mannheim, Germany, said Tuesday that prosecutors have until Sept. 17 to convince him that top military intelligence commanders should not be forced to testify under a grant of immunity.

The Army report also says soldiers used police dogs to intimidate Iraqi detainees as young as 15.

Both reports will be reviewed by the Senate Armed Services Committee in hearings scheduled for Sept. 9.

FOX News' Bret Baier, Ian McCaleb and The Associated Press contributed to this report.