WASHINGTON -- House lawmakers, suspecting that top Pentagon officials covered up the 2004 friendly-fire death of football star and Army Ranger Pat Tillman, want former Defense Secretary Donald Rumsfeld and five generals to testify about the fatal shooting of the San Jose native by soldiers from his unit in Afghanistan.

The Democrats' most tenacious investigator, House Oversight and Government Reform Committee Chairman Henry Waxman of Los Angeles, joined by the panel's ranking Republican, Rep. Tom Davis of Virginia, announced Monday they will ask Rumsfeld, former Chairman of the Joint Chiefs of Staff Richard Myers and retired Gen. John Abizaid, who oversaw operations in Iraq and Afghanistan, to testify at a hearing scheduled for Aug. 1.

Waxman's goal is clear from the title of the hearing -- "The Tillman Fratricide: What the Leadership of the Defense Department Knew."

Rumsfeld and the others could resist testifying before the committee, a media event sure to attract almost every TV camera on Capitol Hill. But Waxman holds a powerful card: He is the only committee chairman who can issue subpoenas without a committee vote.

Still, with Davis' support, it appears Waxman will have the committee's backing to compel the witnesses to appear.

Many lawmakers already believe the Pentagon knew the facts of Tillman's death for weeks, but misled the public by awarding him the Silver Star and spinning a false tale of his dying while fighting enemy forces.

"Who knew what and when?" Rep. Mike Honda, D-San Jose, said Monday. "After years of obfuscation, and likely coverup, an American hero's family and the nation remain inexcusably in the dark. The White House and Department of Defense's refusal to answer this basic question about the death of Patrick Tillman is an affront to the sacrifices of America's warriors."

The committee also wants testimony from Lt. Gen. Stanley McChrystal, who sent a high-priority cable five days after Tillman's death to Abizaid and other top Army commanders, warning that the former NFL safety probably had been killed by friendly fire -- not by the Taliban, as the Army claimed publicly.

The memo, viewed as a smoking gun by congressional investigators, urged Abizaid to immediately contact "POTUS" -- the president of the United States -- "to preclude any unknowing statements by our country's leaders which might cause public embarrassment."

The memo also was sent to Lt. Gen. Philip Kensinger, who oversaw the Rangers, and Gen. Bryan "Doug" Brown, former chief of the Special Operations Command. Both generals, now retired, have been called to testify.

Army spokesman Paul Boyce said he could not comment on whether the current or former officials would agree to appear before Congress. The Army is waiting for more information from the committee, he said.

Waxman's Oversight and Government Reform Committee launched the investigation earlier this year, sifting through evidence gathered by Tillman's family and Army investigators that found that senior Army officers destroyed key evidence, including burning Tillman's uniform and armor-plated vest; warned Tillman's fellow soldiers not to discuss the incident; and later devised a public relations strategy for how to handle the football star's death.

Several Army officers are expected to be disciplined for their handling of the shooting as part of a new Army inquiry. But Tillman's family and House lawmakers believe that top Pentagon officials -- including Abizaid and possibly Rumsfeld -- also were aware of or approved the cover-up.

"How high up did this go?" Waxman asked at the committee's first hearing in April.

Waxman and Davis have accused the Pentagon of blocking their inquiry by refusing to hand over documents, including e-mails and internal memos, about what top generals knew about Tillman's death.

The Pentagon has turned over more than 10,000 pages of documents, but has refused to produce others, with White House lawyers citing executive branch confidentiality. Waxman and Davis, in a letter last week, said the information released thus far "sheds virtually no light on these matters."

"From the very start, the administration has mishandled information about this tragedy and misinformed the American public," said Rep. Tom Lantos, D-San Mateo, a senior Democrat on the committee. "It is high time they came clean and respected the oversight role of Congress in this issue."

© 2007 Hearst Communications Inc.