SAN FRANCISCO -- Barry Bonds attorneys says he will be filling a motion to dismiss the federal perjury and obstruction charges against baseball's all-time home run hitter, claiming misconduct by IRS agent Jeff Novitsky.

In an exclusive interview with KTVU, attorney Michael Raines said he will be targeting Novitsky's creditability. The IRS agent began the investigation into BALCO and the company's distribution of performance enhancement drugs to professional and Olympic athletes.

"I think what I have is very strong worthy evidence that will not be refuted by anything the government has," Raines said. "There has been governmental misconduct in this case of such a character, of such a quantity that no charges against Barry Bonds could ever withstand scrutiny by the court."

Raines claims that Novitsky lied about the reliability of an informant in the search warrant. Novitsky's creditability isn't the only area of the government's case the slugger's defense team is likely to attack.

According to BALCO founder Victor Conte, himself a convicted steroids dealer, Bonds would visit his company's lab on Saturdays and after normal business hours with an entourage that included his trainer, Greg Anderson, and his personal physician, Dr. Arthur Ting.

Anderson had convinced Bonds to use BALCO to develop a dietary and supplement regimen, which Conte designed based on the results of the blood and urine samples.

Conte said Bonds was put through the same tests as other elite athlete clients, including tests to detect the use of 30 different steroids.

Conte hired Quest Diagnostics to do a "quick and dirty" analysis of the samples, to save money. The lab charged Conte $80 per test, rather than its usual $120, after Conte agreed to cut out much of the paperwork and elaborate protocol that typically accompany drug tests.

For instance, Conte said a licensed lab technician never watched Bonds urinate in the bottle. Nor were the samples ever formally sealed, dated and signed by an independent collector. There was also no formal process for who handled the samples at Quest, Conte said.

The indictment does not explain where prosecutors obtained the results, but Conte said they were seized when federal agents raided his lab in September 2003.

"If that's the smoking gun," Conte said, "it doesn't have any bullets."

Criminal defense attorneys not affiliated with the case say the reliability of blood and urine tests are always open to second-guessing even when the forensic handling is done flawlessly.

"There is always an opportunity to attack that kind of forensic evidence through its chain of custody," said attorney William Sullivan, who recently won an acquittal for former federal prosecutor Richard Convertino on an obstruction charge alleging he withheld evidence in a terrorism trial in Detroit.

"You look at how the evidence was preserved, who handled it," Sullivan said. "You can even attack the analysis itself."

Similar chain-of-custody problems exploited by Simpson's lawyers helped derail the prosecution's murder case against him.

Los Angeles County prosecutors argued that DNA testing on blood, hair and fibers collected at the murder scene proved Simpson's blood and the blood of the two victims were present.

But Simpson's defense team was able to cast doubt on whether the evidence tested was the same as that collected at the scene by showing that each piece of DNA evidence was handled by at least three people before it was tested.

The problems with the Simpson evidence prompted law enforcement agencies to adopt more stringent protocols. Few of those protocols were followed in collecting and analyzing Bonds' blood and urine, Conte said.

"I don't think you can prove those were Barry's samples," he said.

Another vulnerable spot in the government's case is Anderson's steadfast refusal to testify against Bonds.

Because federal prosecutors were so adamant that the trainer should go to prison for refusing to testify, the trainer's lawyers -- and most other observers -- believed Anderson's testimony was necessary to indict Bonds.

But Anderson was released from prison Thursday and, according to his lawyers, he never cooperated with the investigation. He could land back in prison, however, if prosecutors decide to call him as a witness during the trial and he refuses to testify.

Criminal defense attorneys said other parts of the government's case against Bonds are ripe for attack -- none bigger than the testimony of his former mistress, Kimberly Bell.

In 2005, Bell told a grand jury investigating Bonds for perjury that the slugger told her he used steroids. But Bell is open to withering cross-examination, lawyers said.

Rains said she was miffed that Bonds didn't pay her the nearly $200,000 she demanded when their 10-year relationship ended in 2003. Bell said she was asking Bonds to keep a promise to buy her house in Arizona, but Rains said the demand amounted to extortion.

The indictment cited 19 instances in which Bonds lied during his grand jury testimony, including several denials that he took performance enhancing drugs.

Little other evidence is presented in the indictment, but that doesn't mean prosecutors don't have something else up their sleeve, legal experts said.

"He testified four years ago and they indicted him Thursday," said New York criminal defense attorney Brad Simon, a former federal prosecutor. That tells me they have a new witness or some new evidence we don't know about that seals the deal."