WASHINGTON (CNN) -- Top lawmakers are demanding to know why the CIA destroyed videotapes of interrogation techniques being used on terror suspects and who knew about it.
CIA Director Michael Hayden said his agency will cooperate fully with the investigation.
"Were there things on those tapes that they did not want to have seen, that did not conform to what the attorney general would allow them to do?" Sen. Jay Rockefeller, D-West Virginia, said Sunday on CBS' "Face the Nation."
CIA Director Michael Hayden will testify Tuesday before the Senate Intelligence Committee, which Rockefeller chairs.
Over the weekend, the Justice Department and the CIA opened a preliminary inquiry into the destruction of the tapes.
The tapes, shot in 2002, showed harsh interrogation techniques of two al Qaeda suspects. The tapes were destroyed in 2005.
The probe is to determine "whether further investigation is warranted," the Justice Department's assistant attorney general for national security, Kenneth L. Wainstein, said Saturday in a letter to the CIA's top lawyer, John Rizzo.
But Sen. Joe Biden, D-Delaware, said the current investigations are not enough. The Democratic presidential candidate wants Attorney General Michael Mukasey to appoint a special prosecutor. Watch what lawmakers have to say about the controversy »
"This is one case where it really does call for a special counsel," Biden told ABC's "This Week."
"I think this leads right into the White House. There may be a legal and rational explanation, but I don't see any on the face of it," he said Sunday.
Rockefeller disagreed, saying, "I don't think there's a need for a special counsel, and I don't think there's a need for a special commission. It is the job of the Intelligence Committees to do that."
Biden also said he does not agree with Hayden's characterization of the tapes' destruction and the interrogations they showed as lawful.
"It appears as though there may be an obstruction of justice charge here, tampering with evidence, and destroying evidence," he said.
But Rep. John Boehner, R-Ohio, said a special counsel isn't necessary because Mukasey has already launched a preliminary investigation.
"We have professional investigators at the Department of Justice who can do this in an even-handed way," Boehner told CNN's "Late Edition with Wolf Blitzer."
So too did Sen. Dianne Feinstein, D-California, a member of the Senate Select Committee on Intelligence who said she has confidence in Mukasey.
"I think this is going to be the first time the new attorney general will have an opportunity to show his independence," she told CNN. "And I think we should let that play out."
Two senior Bush administration officials told CNN that Harriet Miers, who held a series of top posts at the White House starting in 2001, was aware of the tapes and told the CIA not to destroy them.
Rep. Chuck Hagel, R-Nebraska, said he doubts the official explanation.
"Burning tapes, destroying evidence, I don't know how deep this goes. Could there be obstruction of justice -- yes. How far does this go up in the White House?" he said on "Face the Nation."
Sen. Chris Dodd, D-Connecticut, said explanations of the events were "stretching credulity."
But Senate Minority Whip Jon Kyl, R-Arizona, said that while the investigations are necessary, a crime wasn't necessarily committed.
"It may not have been a good idea, but that's different from a crime," Kyl said on CNN's "Late Edition."
White House officials maintain that the president did not learn about the destruction of the tapes until last week.
They say they if the Justice Department and others move forward with a full investigation, they will support it because they want to get to the bottom of this as well. E-mail to a friend