The report comes against the backdrop of a blame game in the US, with intelligence sources privately claiming the Bush Administration exaggerated the threat posed by Sadam Hussein, and vice-versa.
It also comes as the CIA-led weapons search team, the Iraq Survey Group, has so far failed to find any stockpiles of weapons of mass destruction.
Senator Roberts told the Washington Post: "I worry about the credibility of the intelligence community.
"If there's stuff on the fan, we have to get the fan cleaned."
At the centre of the row is a 100-page top secret National Intelligence Estimate (NIE) document which was produced in October 2002.
Such reports usually take months to compile, but a senior intelligence expert was quoted by the newspaper claiming that the NIE was a "cut and paste job", completed in just three weeks and reviewed in only one day.
The document analysed the threat posed by Saddam and the risks of staging an invasion.
I would have thought the problem lay in a White House determined to cherrypick the intelligence advice it was given, not the intel itself. And a president determined to cherrypick what his palace staff fed him.