by Michael Kranish

WASHINGTON -- The day before Senate Watergate Committee minority counsel Fred Thompson made the inquiry that launched him into the national spotlight -- asking an aide to President Nixon whether there was a White House taping system -- he telephoned Nixon's lawyer.

Thompson tipped off the White House that the committee knew about the taping system and would be making the information public. In his all-but-forgotten Watergate memoir, "At That Point in Time," Thompson said he acted with "no authority" in divulging the committee's knowledge of the tapes, which provided the evidence that led to Nixon's resignation. It was one of many Thompson leaks to the Nixon team, according to a former investigator for Democrats on the committee, Scott Armstrong , who remains upset at Thompson's actions.

"Thompson was a mole for the White House," Armstrong said in an interview. "Fred was working hammer and tong to defeat the investigation of finding out what happened to authorize Watergate and find out what the role of the president was."

Asked about the matter this week, Thompson -- who is preparing to run for the 2008 Republican presidential nomination -- responded via e-mail without addressing the specific charge of being a Nixon mole: "I'm glad all of this has finally caused someone to read my Watergate book, even though it's taken them over thirty years."

The view of Thompson as a Nixon mole is strikingly at odds with the former Tennessee senator's longtime image as an independent-minded prosecutor who helped bring down the president he admired. Indeed, the website of Thompson's presidential exploratory committee boasts that he "gained national attention for leading the line of inquiry that revealed the audio-taping system in the White House Oval Office." It is an image that has been solidified by Thompson's portrayal of a tough-talking prosecutor in the television series "Law and Order."

But the story of his role in the Nixon case helps put in perspective Thompson's recent stance as one of the most outspoken proponents of pardoning I. Lewis "Scooter" Libby, the former chief of staff to Vice President Dick Cheney. Just as Thompson once staunchly defended Nixon, Thompson urged a pardon for Libby, who was convicted in March of obstructing justice in the investigation into who leaked a CIA operative's name.

Thompson declared in a June 6 radio commentary that Libby's conviction was a "shocking injustice . . . created and enabled by federal officials." Bush on Monday commuted Libby's 30-month sentence, stopping short of a pardon.

The intensity of Thompson's remarks about Libby is reminiscent of how he initially felt about Nixon. Few Republicans were stronger believers in Nixon during the early days of Watergate.

Thompson, in his 1975 memoir, wrote that he believed "there would be nothing incriminating" about Nixon on the tapes, a theory he said "proved totally wrong."

"In retrospect it is apparent that I was subconsciously looking for a way to justify my faith in the leader of my country and my party, a man who was undergoing a violent attack from the news media, which I thought had never given him fair treatment in the past," Thompson wrote. "I was looking for a reason to believe that Richard M. Nixon, President of the United States, was not a crook."

Thompson was a little-known assistant US attorney in Tennessee when the Watergate investigation in Congress got underway. He had served as campaign manager for the successful 1972 reelection of Senator Howard Baker, a powerful Tennessee Republican.

When the Senate Watergate Committee was established in 1973, Baker became the ranking Republican member and brought Thompson to Washington to serve as minority counsel. Baker, who has been among those now urging Thompson to seek the presidency, did not return a call seeking comment.

John Dean , Nixon's former White House counsel, who was a central witness at the hearings, said he believed that Baker and Thompson were anything but impartial players. "I knew that Thompson would be Baker's man, trying to protect Nixon," Dean said in an interview.

The website of Thompson's presidential exploratory committee, imwithfred.com, suggests that Thompson helped reveal the taping system and expose Nixon's role in the Watergate coverup. And while Thompson's question to presidential aide Alexander Butterfield during a Watergate hearing unveiled the existence of the taping system to the outside world, it wasn't Thompson who discovered that Nixon was taping conversations. Nor was Thompson the first to question Butterfield about the possibility.

On July 13, 1973, Armstrong, the Democratic staffer, asked Butterfield a series of questions during a private session that led up to the revelation. He then turned the questioning over to a Republican staffer, Don Sanders, who asked Butterfield the question that led to the mention of the taping system.

To the astonishment of everyone in the room, Butterfield admitted the taping system existed.

When Thompson learned of Butterfield's admission, he leaked the revelation to Nixon's counsel, J. Fred Buzhardt .

"Even though I had no authority to act for the committee, I decided to call Fred Buzhardt at home" to tell him that the committee had learned about the taping system, Thompson wrote. "I wanted to be sure that the White House was fully aware of what was to be disclosed so that it could take appropriate action."

Armstrong said he and other Democratic staffers had long been convinced that Thompson was leaking information about the investigation to the White House. The committee, for example, had obtained a memo written by Buzhardt that Democratic staffers believed was based on information leaked by Thompson.

Armstrong said he thought the leaks would lead to Thompson's firing. "Any prosecutor would be upset if another member of the prosecution team was orchestrating a defense for Nixon," said Armstrong, who later became a Washington Post reporter and currently is executive director of Information Trust, a nonprofit organization specializing in open government issues.

Baker, meanwhile, insisted that Thompson be allowed to ask Butterfield the question about the taping system in a public session on July 16, 1973, three days after the committee had learned about the system.

The choice of Thompson irked Samuel Dash , the Democratic chief counsel on the committee, who preferred that a Democrat be allowed to ask the question. "I personally resented it and felt cheated," Dash wrote in his memoirs. But he said he felt he had "no choice but to let Fred Thompson develop the Butterfield material" because the question initially had been posed by Sanders, a Republican staffer.

When Dash told Thompson on the day of the hearing that he had agreed to let Thompson ask the question that would change US history, Thompson replied: "That's right generous of you, Sam."

So it was, at the hearing, that Thompson leapt into the national spotlight:

"Are you aware of the installation of any listening devices in the Oval Office of the president?" he asked Butterfield during the national televised hearings.

"I was aware of listening devices, yes, sir," Butterfield responded.

Even as he quizzed Butterfield during the hearing, Thompson said later, he believed the tapes would exonerate Nixon, so he saw no problem in pressing for their release. It was after Thompson heard Nixon incriminate himself on the tapes that Thompson finally decided that Nixon was a crook -- and stopped be ing a Nixon apologist.

"Looking back, I wonder how I could have failed to realize at once . . . the significance of the tapes," Thompson wrote. "I realized that I would probably be thinking about the implications of Watergate for the rest of my life."

Michael Kranish can be reached at kranish@globe.com
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