Kerry's used "testimony" from the VVAW's "Winter Soldier Investigation" as the basis for his war crimes charges. Later investigators were unable to confirm the charges, and in fact discovered that a number of the witnesses were never in Vietnam, never in combat, or were imposters who had assumed the identity of real veterans.
I believe that the investigators all belonged to the Naval Investigative Service, and that their report has disappeared. I've seen no reference to any other refutation of the WSI.
The deception extended to the VVAW leadership. Executive secretary Al Hubbard claimed to have been an Air Force captain wounded piloting a transport over Da Nang in 1966. Hubbard was actually a staff sergeant who had never been assigned to Vietnam.
In defense of Kerry, he quit the VVAW at this time over this issue among others and challenged Al Hubbard repeatedly once he got wind of Hubbard's deception, at that Executive meeting. They almost came to blows.
I don't know if Hubbard got fired from the VVAW over this or if he just faded away.
That the VVAW got fooled by Hubbard does increase the burden of verification on those who believe in the WSI, so this is still a valid point.
I also included this little gem from our own SAMWolf:
More GREAT bumper stickers here. (check all 3 pages!)