The federal judge overseeing a CIA leak case has ordered Time magazine to turn over documents to former White House aide Lewis "Scooter" Libby.

Judge Reggie Walton says Vice President Dick Cheney's former chief of staff is entitled to drafts of articles and other documents from reporter Matthew Cooper because of "a slight alteration" between Cooper's writing and his testimony before a federal grand jury.

The judge says the documents could help Libby's lawyers counter Cooper's testimony in the trial, expected to begin next year. 

Libby is charged with perjury, obstruction of justice and making false statements to federal agents and a grand jury.  The special prosecutor in the case has accused him of lying about his role in the disclosure of an undercover CIA officer's identity.

The prosecutor says Libby disclosed Valerie Plame's identity to reporters in an effort to discredit her husband, Joseph Wilson, a former U.S. ambassador.  Wilson wrote an article in 2003 accusing the Bush administration of twisting intelligence to justify going to war against Iraq.

In addition to Time magazine, Libby's attorneys also sought documents from The New York Times and NBC News.  The news agencies said that the documents were protected by the First Amendment and other laws shielding reporters from the legal process.

But Judge Walton ruled the Constitution does not give journalists the right to refuse to provide information in a criminal case.  He says the reporters in the Libby case were not just reporting on events, but were personally involved in the case itself.

Some information for this report was provided by AP and Reuters.