Wen Ho Lee was fired from the Los Alamos National Laboratory in New Mexico in March for security violations. Prosecutors believe he removed large amounts of material from the laboratory and may have passed them on to China. He is charged with 59 counts of mishandling secret data.

Mr Lee and his wife Sylvia have brought the civil suit against the government because of all the leaks implying that Mr Lee was a spy, which they say will make it very hard for him to get a fair trial.

Numerous, unnamed officials have been quoted in the American press claiming he handed over documents from his work as a nuclear physicist to the Chinese Government. But none of the charges against him mentions espionage. Instead, he is accused only of copying and removing some documents from his work.

The lawsuit says violations of privacy led to his portrayal as a spy. It names the Justice Department, the FBI and the Energy Department and seeks an unspecified amount of monetary damages.

It is aimed at finding out who leaked information such as Mr Lee's employment history, personal financial transactions and the supposed results of lie-detector tests.

"There has been widespread and rampant abuse of this Privacy Act by the agencies we have named in the complaint," Mr Lee's lawyer Brian Sun said.

Mr Lee's daughter, Alberta, said her father would never engage in spying: "My father is not a clear and present danger to the United States. That's a ridiculous idea."

Government response

However Energy Secretary Bill Richardson told reporters that the government had done nothing wrong.

"I believe the lawsuit has no foundation. We have made a concerted effort to protect the privacy of all individuals in this case," he said.

Mr Richardson said all agencies, and especially the Justice Department, had acted responsibly.

Mr Lee is in jail in Albuquerque, awaiting trial. He has denied passing secrets to China and pleaded not guilty to mishandling classified information. China has denied stealing US nuclear secrets.

Mr Lee was accused of downloading classified research on nuclear weapon design, construction, and testing onto 10 portable computer tapes, seven of which are missing.