This is a detailed look at the cover-ups Roberts has been involved in. It's quite interesting...
As chairman of the Senate Select Committee on Intelligence, Sen. Pat Roberts’s (R-KS) duty is “to provide vigilant legislative oversight over the intelligence activities of the United States” and “to assure that such activities are in conformity with the Constitution and laws of the United States.” But on the most important intelligence issues facing Americans – such as the manipulation of Iraq intelligence, warrantless domestic spying, and torture - Roberts has transformed his committee into a “Senate Coverup Committee” for the Bush administration.
Much more:
http://thinkprogress.org/roberts-coverup/