SANTA ANA, Calif. — A reporter for the Washington Times, facing questioning about his confidential sources by a federal judge, refused to cooperate, invoking his Fifth Amendment rights — and even won a public commendation for his reporting from the same judge at a remarkable hearing here yesterday.

However, the turnabout was something of a Pyrrhic victory for the journalist, William Gertz, as he learned moments before the court session that the Justice Department plans to subpoena him before a grand jury investigating leaks of classified information. That development means Mr. Gertz faces a potentially broader inquiry into his reporting and his sources than was mulled by Judge Cormac Carney, who had ordered Mr. Gertz to testify about a single article he wrote in 2006 predicting new charges in a Chinese espionage case the judge was overseeing.

“Today’s hearing shows that First Amendment press freedoms are under assault. Confidential sources are the lifeblood of a free press, independent of government control,” Mr. Gertz said in a statement he read to reporters after the judge ruled. “Efforts by government to compel reporters to disclose news sources must be resisted.”

Yesterday’s court session took place over strident objections from the Justice Department. A federal prosecutor who investigated the alleged grand jury leaks, Jay Bratt, urged the judge to put off the hearing so the government could pursue its newly invigorated investigation.

“The request to stay the proceedings is denied,” Judge Carney said. “This has been outstanding for a long period of time and I need to bring my investigation to a conclusion.”

When Mr. Bratt said the Justice Department believed the judge’s inquiry raised “serious separation-of-powers issues,” Judge Carney’s exasperation with the government became evident. He noted that Mr. Bratt had earlier received approval of the Justice Department to question Mr. Gertz, but recently retreated from that commitment, on the advice of senior officials.

“I asked you to the prom and you said you’d go. Then you left me at the dance,” the judge complained.

The judge also denied a request to stay the hearing so the government could appeal to the 9th Circuit, though he did excuse Mr. Bratt from the courtroom to advise Washington of the developments.

The session began with Mr. Gertz’s attorney, Charles Leeper, trying to convince Judge Carney that Mr. Gertz’s article did not contain grand jury information and that Mr. Bratt’s leak investigation, which involved more than 500 interviews, failed to take account of information the prosecution disclosed publicly at pretrial hearings.

Judge Carney said he was convinced, as Mr. Bratt’s probe found, that information leaked in violation of court rules made it into Mr. Gertz’s story. “I do believe it reveals matters that the U.S. attorney presented to the grand jury,” the judge said. “It predicted with 100% accuracy the charges that would be brought.”

In fact, as Mr. Leeper pointed out, Mr. Gertz’s article predicted the filing of an espionage charge, which never came to pass.

A defense attorney who brought a motion objecting to the alleged leaks, Stanley Greenberg, told the judge that the reporter shouldn’t benefit from being wrong. “I don’t think he gets brownie points for publishing information that turns out to be inaccurate that should not have been disclosed to him in the first place,” the lawyer said.

When Judge Carney began questioning Mr. Gertz, Mr. Bratt exited the courtroom. When the reporter was asked whether he would “voluntarily” name his sources, he replied, “No, sir.” In response to a series of other questions, Mr. Gertz read a prepared statement invoking his right against self-incrimination.

After hearing more argument from the lawyers, Judge Carney, who was adamant about proceeding with yesterday’s session and putting Mr. Gertz on the witness stand, made an odd turn. Seemingly reading from a prepared text, he declared that the public’s interest in investigative reporting outweighed the court’s interest in determining the identity of those who disclosed an indictment prosecutors planned to seek from the grand jury. He went on to praise Mr. Gertz for informing the public about the threat posed by espionage, particularly spying undertaken by China.

No details were offered in open court about the focus of the grand jury that may investigate classified leaks to Mr. Gertz, who has made a specialty of obtaining and publishing classified information. There is no obviously classified information in his May 16, 2006, article about the spy case. However, a book by Mr. Gertz published later that year, “Enemies,” discusses a National Security Agency telephone intercept said to be critical to the case, as well as an informant who “worked within the Chinese military and security establishment” and whose statements to the CIA reportedly triggered the spy probe.

Such information is usually highly classified, though the contents of the phone call were discussed publicly at the trial of one of the defendants last year.

In an ironical twist, while Judge Carney let Mr. Gertz off the hook yesterday, the judge’s insistence on pressing forward with the hearing seems to have placed the reporter in even greater jeopardy by stirring the Justice Department to reactivate a dormant criminal investigation of his work.