Troy Ellerman pleaded guilty to making the leak, lying about it, obstructing justice and disobeying a court order not to disclose grand jury information, according to a plea agreement filed today in federal court in San Francisco.

Ellerman let Chronicle reporter Mark Fainaru-Wada take verbatim notes "of the transcripts of grand jury testimony of baseball players Jason Giambi, Barry Bonds and Gary Sheffield" in November 2004, according to a criminal complaint filed today.

Federal prosecutors had been searching for the source of the leaks, which led to contempt findings against two Chronicle reporters. Fainaru-Wada and Lance Williams wrote in December 2004 that Bonds told the grand jury he might have unknowingly used substances containing steroids. Bonds, who has denied using steroids, said he thought the substances were flax seed oil and a legal ointment, according to the articles.

Ellerman was a defense attorney in the criminal case against employees of Bay Area Co-operative Laboratory, known as Balco, the California lab at the center of a federal probe into steroid use among athletes.