Corporal Tillman died on April 22nd 2004 in Afghanistan at the age of 27. Despite knowing within hours of his death that he was killed as a result of friendly fire, the US army did not correct reports that he had died a heroic death up until a month later.
Democrat Henry Waxman responded to the claims of Kevin Tillman, himself a member of the elite Rangers regiment, by saying the army had spun "sensational details and stories".
Another soldier giving evidence to the house committee was Private Jessica Lynch, who was badly wounded during an ambush by insurgents north of Basra, Iraq, in 2003.
She was subsequently rescued by US troops from an Iraqi hospital, but she has accused the Pentagon of exaggerating her own heroic role in the initial ambush.
"The bottom line is the American people are capable of determining their own ideals of heroes and they don't need to be told elaborate tales,'' she said.
Pat Tillman's mother Mary meanwhile said the suggestion that then defence secretary Donald Rumsfeld did not know her son died from friendly fire was "ludicrous".
The US army's own report concluded last month that officers had made mistakes in reporting Corporal Tillman's death, but that no criminal wrongdoing had taken place.
Corporal Tillman's death was a major story in the US and elsewhere around the world after he gave up a multi-million dollar American football contract to enlist in the army after the September 11th terror attacks.
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