The Washington Post reviewed 2,000 pages of Army investigation into the death of pro football player-turned Afghan war volunteer Pat Tillman, who was eventually found to have died from friendly fire, and found:
[O]fficers made erroneous initial reports that Tillman was killed by enemy fire, destroyed critical evidence and initially concealed the truth from Tillman's brother, also an Army Ranger […]
An initial investigation found fratricide just days later. Top commanders within the U.S. Central Command, including Abizaid, were notified by April 29 -- four days before Tillman's memorial service in San Jose, where he was given a posthumous Silver Star Award. Jones concluded that Tillman, who was bravely leading his fire team into battle, was given the award based on what he intended to do.
The family learned about Tillman's fratricide over Memorial Day weekend, several weeks later.
Link via Sploid.