Watergate conspirator G. Gordon Liddy regaled a federal jury in Baltimore yesterday with details of the covert political mission that eventually brought down a president, telling how he shredded documents and hundred-dollar bills after the famous 1972 break-in and matter-of-factly warned his wife that he was headed to jail.

But as to the purpose of the botched burglary at the Democratic National Committee, Liddy said he learned only years later the explanation he now believes is true - that the burglars were secretly directed by then-White House counsel John W. Dean III to find pictures that could have linked Dean's future wife to a call-girl ring.

It is a theory that has landed Liddy in U.S. District Court in Baltimore, defending himself against a $5.1 million defamation lawsuit.

Ida "Maxie" Wells contends the revisionist theory of Watergate that Liddy now supports falsely portrays her as helping to run the alleged call-girl operation from the DNC, where she worked as a young secretary at the time of the break-in.

Testifying yesterday, Liddy said orders from Nixon campaign director Jeb Stuart Magruder to send his team of CIA-trained burglars into Democratic headquarters never fully made sense to him because there was little sensitive information kept there at the time and it was not a target for the "black bag" political espionage operations he had planned for that spring.

"Absolutely not," Liddy testified, noting that he had intended to break into the campaign headquarters of the two top Democratic presidential candidates and to stake out the Democrats' national convention in Miami. "There was nothing to be gained at the Watergate, and there was no plan to go in there."

In his first-hand account of the history, Liddy told jurors yesterday about the hardships of prison and his subsequent career as a talk radio host and occasional television actor. He also told how he came to believe that Dean - who in the history books became Watergate's whistleblower hero - was secretly directing the burglars.

Dean has denounced the alternate theory linking Watergate to a call-girl ring or to his wife, Maureen. The Deans also sued Liddy in the early 1990s, but the case was dismissed.

Wells' 1997 lawsuit has twice been dismissed by a federal judge in Baltimore but was reinstated each time by an appeals court. The case also has been to trial once before - a jury hearing the case early last year deadlocked 7-2 in favor of Liddy.

Liddy gave a more subdued performance yesterday than at the first trial, where he barked his name in military parlance at the beginning of his testimony - "Liddy: that's Lima, India, Delta, Delta, Yankee" - and summed up his first lengthy public testimony on Watergate with the explanation: "My father didn't raise a snitch or a rat."

The former FBI agent, who spent almost five years in prison for his role as the head of the political espionage team in Watergate, detailed his work for the Nixon White House and told what happened in the hours and days after the five burglars working for him were arrested inside the DNC.

When he went home that night, Liddy testified, he woke up his wife and told her something had gone wrong.

"'My guys got caught tonight,'" he said. "'I think I'm going to jail.' And then I went to sleep."

Later, at his own office, Liddy said, he shredded reams of documents as well as $1,300 in consecutively numbered hundred-dollar bills.

Liddy said he long accepted the conventional theory of Watergate. But he offered a detailed accounting of the evidence he said convinced him that Dean was the unseen hand behind the burglary.

He said his investigators in the 1990s talked to a stockbroker for the call-girl ring's de facto bouncer, a former FBI agent named Lou Russell.

The broker said Russell, who typically lived close to the bone, suddenly had about $25,000 to invest between late 1972 and early 1973 - money Liddy suggested came from GOP campaign cash that Dean never accounted for.