After assessing the allegations against Sanchez and taking sworn statements from 37 people involved in Iraq, the Army's inspector general, Lieutenant General Stanley E. Green, concluded that the allegations were unsubstantiated, said the officials who were familiar with the details of Green's probe.
Green reached the same conclusion in the cases of two generals and a colonel who worked for Sanchez.
The officials who disclosed the findings spoke on condition of anonymity because Congress has not yet been fully briefed on Green's findings and the information has not yet been publicly released. Green had scrutinized the actions of Sanchez and 11 other officers.
Iraqi detainees at Abu Ghraib were physically abused and sexually humiliated by military police and intelligence soldiers in the fall of 2003. Photos of some of the abuse created a firestorm of criticism worldwide.
Congress has hotly debated the question of accountability among senior Army and Defense Department officials who were in positions of responsibility on Iraq detention and interrogation policy. Some Democrats have accused the Pentagon of placing all blame on low-ranking soldiers.
In a statement yesterday that did not mention specific cases, Senate Armed Services Committee Chairman John Warner, Republican of Virginia, said that as soon as all Pentagon assessments of accountability are complete, he will hold a hearing ''to examine the adequacy of those reviews" and to hear senior civilian and military officials address the issue.
Warner said he strongly agrees with one investigation report that concluded last year that commanders should be held accountable for their action or inaction and that military as well as civilian leaders in the Pentagon ''share this burden of responsibility."
The office of Senator Carl Levin of Michigan, a top Democrat on the Senate Armed Services Committee, declined to comment.
Some have said the blame should rest with Defense Secretary Donald H. Rumsfeld, although none of the 10 investigations done so far has concluded that he was directly at fault.