Brian Ross and Avni Patel Report:
Fred Thompson has made much of his role 30 years ago as a young Senate lawyer helping to lead the investigation of the Watergate scandal and President Richard Nixon.
But a much different, less valiant picture of Thompson emerges from listening to the White House audiotapes made at the time, as President Nixon plotted strategy with his aides in the Oval Office.
Thompson's job on the Watergate committee was to lead the Republican side of the investigation. He was appointed by his mentor, Sen. Howard Baker of Tennessee, who is now co-chair of Thompson's 2008 presidential bid.
Photos: Nixon on Tape: Thompson 'Dumb as Hell'
When Nixon's aide H.R. Haldeman told Nixon of Thompson's appointment, Nixon was less than impressed.
"Baker has appointed Fred Thompson as minority counsel," Haldeman is heard saying on one tape.
"Oh sh--, that kid," Nixon responds.
"I guess so," Haldeman replies.
Nixon worried that Thompson's Democratic counterpart, Sam Dash, would outsmart Thompson.
"Well, Dash is too smart for that kid," Nixon says on another tape from March 16, 1973. The existence of the tapes were publicly revealed by a question from Thompson at a Watergate hearing and led to the president's resignation. They are preserved at the National Archives in College Park, Md.
"Sure. Runs circles around him," agrees an aide, John Dean.
As the investigation picked up speed, Nixon grew increasingly concerned about whether Thompson could stand up to the Democrats.
In this May 1973 recording, he shared his concern with then-chief of staff Alexander Haig.
"He's talking to Fred Thompson. I said you're not --," Haig begins.
"Oh sh--, he's dumb as hell. Fred Thompson," Nixon interjects. "Who is he? He won't say anything."
In another conversation some weeks later, Nixon and his advisers were still describing Thompson as not very smart but at least beginning to play ball.