Vets testified (Winter Soldiers hearings in Detroit) to what they'd done in Vietnam.
They asked Kerry to represent them to Congress.
Kerry did so, summarizing to Congress what THEY, the vets, had said THEY, the vets, had done (atrocities).
Republican senator Hatfield ordered the vets' testimonies into the Congressional Records and then ordered the Naval Investigation Service to investigate the vets.
The NIS did so and concluded they could neither confrim nor deny the vets' confessions.
At no time did Kerry accuse the vets of atrocities. Full statement;
http://www.nationalreview.com/document/kerry20040423104...Notice all the "COMMENDABLE" and suchlike remarks the chairman spoke to Kerry. Funny how 30+ years later the Republican Party is now smearing and condemning Kerry.