A former U.N. arms inspector from Australia named Rod Barton has written a memoir titled "The Weapons Detective." In it, he describes how the US suppressed information that debunked claims about "bioweapon trailers."
At one point, former U.N. arms inspector Rod Barton says, a CIA officer told him it was "politically not possible" to report that the White House claims were untrue. In the end, Barton says, he felt "complicit in deceit."
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Testing the equipment in early May 2003, U.S. experts found no traces of biological agents, and later that month the U.S. fact-finders filed their negative report from Baghdad.
But on May 29, Bush assured Polish television: "We found the weapons of mass destruction. We found biological laboratories." Then national security adviser Condoleezza Rice and Secretary of State Colin Powell later made similar statements. As late as January 2004, Vice President Dick Cheney called the trailers "conclusive evidence" of Iraqi WMD, one of the reasons given for invading Iraq.
http://news.yahoo.com/s/ap/20060513/ap_on_re_mi_ea/iraq_wmd_trailers