SAN FRANCISCO -- Even if Giants slugger Barry Bonds is charged with lying to a grand jury, it will be hard to convict him, former federal prosecutors and other lawyers said.
"It is a lot tougher to make a perjury case than most people think because it takes more than just proving that the person made a statement that was untrue," said Adam Hoffinger, a criminal defense lawyer in Washington D.C. "The government has to prove that he knowingly and willfully lied about a material fact -- it can't be a mistake, there has to be intent."
A federal grand jury is investigating whether Bonds committed perjury when he testified in 2003 that he never used steroids, a person with knowledge of the probe told The Associated Press on Thursday night. The person spoke on condition of anonymity because of the secrecy of the investigation.
Bonds, who is chasing Hank Aaron's home run record, was granted immunity to testify truthfully before a grand jury in December 2003 investigating a Northern California steroid distribution ring based at the company called the Bay Area Laboratory Cooperative, or BALCO.
According to excerpts of testimony previously reported by the San Francisco Chronicle, Bonds testified that he used a clear substance and a cream given to him by a trainer convicted in the case, but said he didn't know they were steroids.
Bonds testified that Greg Anderson, his personal trainer, told him the substances were the nutritional supplement flaxseed oil and an arthritis balm.
Anderson and three others, including BALCO founder Victor Conte, have pleaded guilty to distribution charges.
Erwin Cherminsky, a Duke University criminal law professor, said the excerpt he has read of the recently published book "Game of Shadows," which details extensive and knowing steroid use by Bonds, "certainly suggests he lied under oath."
The book's publication prompted Major League Baseball Commissioner Bud Selig to launch an investigation into steroid use among big league players.
Michael Rains, Bonds' attorney, did not return a telephone call Friday.
Experts said prosecutors will need some evidence other than Bond's testimony that he didn't know what he was taking in order to prove he purposely lied to mislead the grand jury.
One key witness in any perjury case against Bonds could be his ex-mistress Kimberly Bell, who has said Bonds told her he took steroids.
"She could also testify to bouts of rage, sexual problems and other behavior consistent with steroid use," criminal defense attorney Daniel Horowitz said. "If he said he didn't use and he knowingly used them, he is in trouble and Bell can help the government's case."
Other former prosecutors said that Bell could face credibility issues and be portrayed as a scorned lover with financial problems. Bell's attorney could not be reached for comment.
The fact that the U.S. attorney's office in San Francisco has convened a grand jury to look into Bond's steroids testimony means the slugger is probably in trouble, he said.
"They wouldn't go in front of the grand jury unless they had something to go after," Horowitz said.
A spokesman for the U.S. attorney's office didn't return a telephone call seeking comment.
Though perjury charges are relatively rare, they do occur.
Chris Webber of the Philadelphia 76ers pleaded guilty in 2003 for lying to a federal grand jury about perks that players received when he was at the University of Michigan. Webber ended up paying a $100,000 fine and was placed on two years' probation after pleading to the lesser charge of contempt.
Still others said the government could be motivated to go after Bonds to serve as a high-profile example of a witness breaking an immunity deal.
"They could be looking at the immunity promise and maybe Bonds flaunted it with his testimony," said Ed Davis, a former federal prosecutor who now defends white collar cases. "You just can't have people walking in and getting immunity and flaunting it."
Davis said he never prosecuted anybody for perjury during his time as a prosecutor in the 1970s and that all the perjury cases against his defense clients were dropped.
"When I was a prosecutor, there were a lot of strong cases that I looked at hard but ultimately dropped," he said. "It's hard to prove intent."