WASHINGTON (AP) _ Lawyers for an FBI scientist who publicly criticized the bureau's crime lab say the Justice Department is conducting a retaliatory investigation of him.

FBI crime lab supervisor Frederic Whitehurst has been called for an interview today by a special department investigator looking into a leak of some of Whitehurst's allegations about lab employees.

In a letter to Attorney General Janet Reno, lawyer Johnnie L. Cochran Jr. protested it was ``a retaliatory interview, which could result in his termination from employment, his indictment for an alleged crime and the complete destruction of his well-earned reputation.''

Cochran, who recently defended ex-football star O.J. Simpson, joined Whitehurst's team of lawyers this week.

Justice Department spokesman Carl Stern said, ``There is no criminal investigation looking into the conduct of Frederic Whitehurst. There's an administrative inquiry in connection with the leak of Whitehurst's communications with the department to a writer from Playboy magazine.''

Beginning last fall, Whitehurst alleged that a pro-prosecution bias and mishandling of evidence may have tainted crime lab work or testimony on several high-profile federal cases. These include the World Trade Center bombing, the mail-bomb killing of a federal judge and a civil rights lawyer, and the Oklahoma City federal building bombing.

The allegations by Whitehurst, once rated by the FBI as its top expert on bomb residues, prompted the Justice Department's inspector general to assemble an international team of experts late last year to review the lab's work. The review is still under way.

Meantime, Whitehurst was called to an interview by Special Investigative Counsel Joseph C. Hutchison, who was brought here from the Connecticut U.S. attorney's office to conduct the leak investigation.

On Feb. 13, Hutchison wrote Whitehurst's lawyers that ``there is substantial reason to believe that your client ... is responsible for the unauthorized release of work-related information to Jeff Stein,'' a freelance writer who produced a yet-to-be-published article for Playboy.

Stern said Playboy wrote the department to check the article's facts, which allowed officials to learn that the article would contain information and allegations about FBI employees that is protected from public release by the Privacy Act.

Hutchison wrote that Whitehurst could invoke his right against self-incrimination at the interview and would not be offered immunity from prosecution.

``That's boilerplate warning language in case he said something incriminating,'' said a senior Justice official, who spoke on condition of anonymity. ``We don't contemplate a criminal case. This is over whether he should be disciplined administratively.''

Two other senior Justice officials denied there was any intent to fire Whitehurst.

But Cochran wrote Reno that Hutchison's letter, coupled with an FBI requirement that Whitehurst gain approval from his superiors before discussing work-related information with his attorneys, ``demonstrate the biased nature of the current investigation'' and deprive Whitehurst of ``the benefit of informed counsel.''

``It demonstrates the inability of the Department of Justice to investigate itself or protect its own whistleblowers,'' Cochran wrote. He requested the department disqualify itself from investigating Whitehurst.