Citing a need to protect national security, a judge drew strict limitations on depositions Monday in a defamation lawsuit filed against Wen Ho Lee by the Energy Department's former intelligence chief.

In the suit, Notra Trulock contends Lee and two investigators accused Trulock of racial profiling in an investigation of security breaches at the Los Alamos National Laboratory, where Lee was a nuclear scientist.

The two investigators, former Los Alamos counterintelligence chief Robert Vrooman and Trulock's predecessor, Charles Washington, also are named in the suit.

Government attorneys asked U.S. District Judge Thomas Jones to postpone a deposition of Lee and limit the discovery process while officials determine what classified information might be involved and how nuclear secrets should be handled.

"This is some of the most sensitive classified information the government holds — its nuclear weapons and comparable information," said Justice Department attorney Anne Weismann. "That, in our view, compels the court to go carefully."

The judge said he was sensitive to the national security interests but said fundamental issues could be dealt with without risking the disclosure of nuclear secrets.

Vrooman and Washington allegedly stated in depositions that Trulock had singled out the Taiwanese-born Lee because of his race. Lee's supporters then posted the depositions on a Web site.

"At its base, ... this is a pair of lawsuits in which the plaintiff alleges that these defendants called him a racist," said Jones. "The truth or falsity of the statements are what this case is all about."

Jones said he would allow attorneys to begin building their cases on whether the statements by Vrooman and Washington were defamatory, what Lee and his backers did to spread the statements and whether Trulock is a public figure who would enjoy less legal protection from slanderous statements.

He said they had to avoid specifics of how the investigation was conducted and any queries that might draw in classified nuclear secrets. He also granted the government's request to postpone a deposition of Lee until at least next month.

Lee was indicted on 59 felony counts for transferring nuclear weapons information to portable computer tapes, charges stemming from an investigation into possible Chinese espionage. Lee was not charged with spying and denied giving information to China.

Lee eventually pleaded guilty to one felony count of downloading sensitive material. The judge in that case said he was misled by prosecutors and apologized to Lee for nine months he spent in solitary confinement.

Lee has sued the government for allegedly leaking information to the media to portray the Taiwan-born scientist as a Chinese spy.