But one of the testiest moments came at the hands of Republicans. A sharp exchange occurred when Sen. John McCain, the Arizona senator, pushed aside the panel's stance that some of their answers should be measured because of pending investigations.
The heated tone continued with the next questioner, Sen. Edward Kennedy (D.-Mass.), who asked Rumsfeld when he became aware of the allegations of abuse.
Sen. Mark Dayton (D-Minn.) also blasted Rumsfeld and Gen. Richard B. Myers, chairman of the Joint Chiefs of Staff, for trying to suppress news reports of the scandal, prompting an angry exchange.
"Is that the standard position of the high command of this country to try to suppress news reports?" Dayton asked Myers. Rumsfeld said that it is not unprecedented for the military to ask the media to sit on information in service of national interest. "It's not against our history, it's not against our principle," he said.
Dayton did not back down and criticized Rumsfeld for withholding information of the photographs, even though the secretary made an appearance on Capitol Hill the day the story became public.
Critics have accused administration officials - particularly Rumsfeld - of acting too slowly to address the abuses they said they first learned about in January. At today's hearing, Rumsfeld was confronted with the International Committee of the Red Cross' statements that U.S. officials knew about the abuses last year and had alerted American authorities in detailed reports.
Today, Rumsfeld said he would turn over to the committee all U.S. records related to the abuses.
Rumsfeld also repeated that he did not know about the abuses until Jan. 16, when U.S. Central Command announced publicly that it had launched an investigation over allegations of abuse.
Although he said he was blindsided by events, and did not see any photographs until months later, Rumsfeld acknowledged that he failed to keep the president and other lawmakers aware of the serious abuses taking place in Iraq.
"Let me be clear: I failed to recognize how important it was to elevate a matter of such gravity to the highest levels, including the president and the members of Congress."
The abuses occurred last year between October and December, Myers told the House committee. He flatly denied that the Pentagon applied pressure to get more results through interrogation, resulting in abuses. Instead, he said that a leader was not needed to tell those involved that the abuses were "immoral" and "unethical".
"This is a failure of individuals," he said.
Rep. Gene Taylor (D-Miss.) criticized Rumsfeld's management of the war, saying the photographs represent only the latest in a string of American failures in Iraq. Taylor grew emotional, saying he shares in those failures as a congressional member who voted for the war.
"You're obviously a smart man," Taylor said. "How is someone so smart and so detail-oriented, why did it take from January to May to find out about this? I sent those kids off to get killed. I share in the responsibility."
The scandal has provoked several Democrats, including Massachusetts senator and presidential hopeful John Kerry, to call for Rumsfeld's resignation. Several newspapers, including the New York Times today, also wrote editorials saying the Defense secretary should step down. The Republican leadership also has sharply criticized Rumsfeld.
But Rumsfeld still has backing from his most important ally: President Bush. The president on Thursday insisted that he was sticking with Rumsfeld as his Defense secretary.
"Secretary Rumsfeld is a really good secretary of Defense," Bush said. "Secretary Rumsfeld has served our nation well. Secretary Rumsfeld has been the secretary during two wars He's an important part of my Cabinet, and he'll stay in my Cabinet."