SAN FRANCISCO, California - Jurors in the Barry Bonds trial will never hear a recording of Bonds' ex-business manager telling his surgeon Bonds could be implicated in a steroids scandal following a raid on a California laboratory.
US District Judge Susan Illston called the 2003 garbled tape "barely intelligible" and said she was concerned that the tape had appeared at the last minute.
The ruling was a blow to prosecutors, who had hoped to use the tape to bolster the credibility of a key government witness.
The ex-business manager, Steve Hoskins, told jurors that he had discussed Bonds and steroids about 50 times with Bonds' orthopedic surgeon, Dr Arthur Ting.
He had attempted to secretly record one of those conversations, he said, hiding a cassette recorder in his jacket pocket. Later he couldn't find the tape and assumed the recorder had malfunctioned.
After Ting took the stand and flatly denied ever having any conversations about Bonds and steroids, Hoskins apparently found the tape and gave it to the government.
But Judge Illston said it was too late.
"To add the tape at this stage in the proceedings would raise issues related to the authenticity," she said in a hearing without the jury present.
The government released a transcript of the conversation as part of its effort to admit the tape as evidence.
In the transcript, Hoskins tells Ting that federal agents raided the Bay Area Laboratory Co-operative (BALCO) the previous night and raises concerns about what that means for Bonds.
US home run king Bonds is on trial on charges of perjury and obstruction of justice in connection with his 2003 testimony to a grand jury investigating BALCO.
The former San Francisco Giants slugger told the grand jury he had taken substances he believed were flaxseed oil and arthritis balm but denied knowingly taking performance-enhancing drugs.
In the transcript of the tape, Hoskins says he was warned about the raid by a female football player who was friends with BALCO founder Victor Conte.
"So she calls me and tells me OK, you better ... call Greg or try to get a hold of Barry whatever cause ... they're arresting Victor right now (and) searching the lab."
Hoskins tells Ting he was thrown that others knew about Bonds' steroid use. "All of them already knew ... that Barry was already juicing," he says.
"I didn't have no clue that somebody else knew," he says later in the conversation. "I thought I knew and about five other people were around."
Ting's response is muffled, ending with the words "about Bonds."
"Yeah and I didn't know Victor," Hoskins replies, referring to the BALCO founder.
Ting's responses are mostly inaudible, according to the government transcript.
The prosecution argued the significance of the tape was not the content but the fact that the conversation had taken place, despite Ting's denials.