A reporter for The Advocate will not have to appear in court as part of a Baton Rouge lawyer’s federal defamation lawsuit against a police detective.

In quashing the motion that would have required reporter Jim Mustian to testify about an article he wrote, U.S. Magistrate Judge Richard Bourgeois Jr. said whatever details lawyers want from Mustian could be obtained from Mustian’s sources in the story — namely Baton Rouge Cold Case Detective John Dauthier and other police records.

The plaintiff, Joel Porter, “has not sufficiently demonstrated that any information Mr. Mustian could provide is relevant,” Bourgeois said. “As such, the necessity of such information is questionable at best. The chilling effect of such compelled disclosure, however, would infringe upon the protection afforded to the press by the First Amendment.”

The lawsuit stems from a January article that Mustian wrote for The Advocate about the unsolved murder of Joel Porter’s wife, Denise Washington Porter, who was killed in 1985 and whose death remains unsolved. The article quotes multiple documents, including a search warrant, which say that Joel Porter — a well-known attorney who has run for Baton Rouge City Court judge — was a suspect in the slaying and describe what led police to think he might be linked to the death. But Porter’s lawyers have since accused Dauthier of tarnishing Porter’s name by convincing Mustian to publish details about the lawyer to make him look like a more convincing suspect than he actually was.

Mustian became part of the case, even though he has never been a defendant in the lawsuit, because Porter’s lawyers wanted him to testify about an investigative file quoted in the piece.

They claimed that by asking him about the file, they could obtain more context for their case.

But Mustian’s lawyer, Scott Keaty, has argued that getting Mustian to testify about his sources is nothing more than scouting for information that could have been obtained another way and treads upon state and federal laws protecting reporters’ privilege.

“Private litigants cannot use the press as a research tool,” Keaty told Bourgeois in July.