A bipartisan panel of senators has concluded that former defense secretary Donald H. Rumsfeld and other top Bush administration officials bear direct responsibility for the harsh treatment of detainees at Guantanamo Bay, and that their decisions led to more serious abuses in Iraq and elsewhere. In the most comprehensive critique by Congress of the military's interrogation practices, the Senate Armed Services Committee issued a report yesterday that accuses Rumsfeld and his deputies of being the authors and chief promoters of harsh interrogation policies that disgraced the nation and undermined U.S. security. The abuse of detainees in U.S. custody cannot simply be attributed to the actions of 'a few bad apples' acting on their own," the report states. "The fact is that senior officials in the United States government solicited information on how to use aggressive techniques, redefined the law to create the appearance of their legality, and authorized their use against detainees." Human rights and constitutional law organizations have urged further action, ranging from an independent commission to prosecutions of those involved in authorizing the interrogations. Michael Ratner, president of the Center for Constitutional Rights, which has helped defend detainees at Guantanamo, said the committee report is valuable because "it's official, it's bipartisan. It's open and explicit, going right to Rumsfeld and having Rice involved," Ratner said. "It breaks new ground in saying that the [torture] techniques basically don't work . . . that they're actually designed to elicit false confessions."