Federal investigators deceived former Los Alamos physicist Wen Ho Lee into agreeing to a polygraph examination last February and then mistreated him throughout the so-called lie detector session, causing him to fail, his lawyer argued in a closed hearing before a federal judge.

A transcript of the Dec. 29 hearing, newly released by the Justice Department, reveals some details of the government's case against Lee but also shows that the FBI used highly aggressive tactics in pursuing him.

FBI agent Robert A. Messemer acknowledged during the bail hearing in New Mexico before U.S. District Judge James A. Parker that investigators misled Lee about the polygraph session, telling him they needed his "help" with an investigation into China's alleged theft of information about America's W-88 nuclear warhead. Only moments before the test did the investigators inform the 60-year-old scientist that he was an espionage suspect.

Messemer conceded under questioning by Lee's attorney that the emotional impact of such a last-minute revelation could cause a subject to fail.

Lee has not been charged with passing secrets to any country. But after three days of open and closed hearings, Parker ordered him held without bail pending trial on 59 counts of mishandling U.S. nuclear secrets. In particular, the judge cited Lee's failure to provide information about seven missing computer tapes containing a trove of secrets, which Lee claims to have destroyed.

According to the transcript, which was heavily edited to protect national secrets, Lee reluctantly took the polygraph not once but twice on Feb. 10, 1999. The first test was inconclusive. In an attempt to resolve questions raised by the examiner, Lee admitted that he actually gave more information than he had previously acknowledged to Chinese scientists at meetings in Beijing in 1986 and 1988. He then retook the test, and failed.

Messemer, in the face of tough questioning about the FBI's tactics, stood by the validity of the testing and said Lee's failure was consistent with "a 16-year history of deceiving the FBI."

With Lee facing a possible life sentence, both sides in the high-profile case had sought public release of the transcript to bolster arguments they made in open court.

Lee's family and supporters in the Chinese American community believe the transcript supports their contention that the FBI railroaded the Taiwan-born scientist after singling him out as a suspect on the basis of ethnicity.

Another classified transcript, released two weeks ago, showed that FBI agents also lied to Lee in a harsh interrogation last March, telling him that he had failed an earlier polygraph administered by the Department of Energy in December 1998 and pressing him to confess to espionage. Actually, he had passed that exam, and he staunchly maintained his innocence.

FBI spokesman John Collingwood said last night that "the judge heard all the evidence" and "his findings and ruling speak for themselves and came without criticism of any testimony or actions by the government."

Victoria Toensing, a Washington criminal defense attorney and former Justice Department official, said law enforcement officials are "permitted to use a ruse" to elicit information from a suspect. "It is an accepted practice," she said. "It is not unethical."

But in this case, she added, deceiving Lee about the purpose of the polygraph might not have been very smart, because the last-minute revelation that he was a suspect could have invalidated the results.

Defense attorney Mark Holscher pressed Messemer on this point throughout the bail hearing, asserting that Lee was lied to and mistreated throughout the polygraph session. Holscher said Lee was in pain during the tests because a wire to measure his physiological responses was improperly attached and made his thumb go numb.

Messemer, in response, traced a history of alleged deception by Lee dating to 1983. "Doctor Lee has repeatedly inserted himself into highly questionable circumstances, highly suspicious activities," the FBI agent said.