Roger Clemens and his attorney, Rusty Hardin, arrive at federal...

Roger Clemens and his attorney, Rusty Hardin, arrive at federal court in Washington. (April 16, 2012) Credit: AP

WASHINGTON -- A forensic toxicologist testified Tuesday in the Roger Clemens perjury trial that saved needles and swabs that tests show contain steroids and the star pitcher's DNA are "unreliable" evidence.

Bruce Goldberger of the University of Florida's toxicology laboratory disparaged the government theory that the syringes and cotton balls that Clemens' former trainer Brian McNamee said he stashed in a beer can after injecting Clemens proved the pitcher had used steroids.

"The government's theory cannot be proven," Goldberg said under questioning by defense attorney Rusty Hardin. "I have never seen evidence like this being used by prosecution to link a person to the drug." He added, "I am saying the weight of the evidence in this case is lacking because of the potential for contamination."

Goldberger conceded under cross-examination by Assistant U.S. Attorney Daniel Butler that he does not know for certain that contamination occurred, and no test is available to show transference of substances from one item to another.

He also said he was not contesting the validity of tests done by the FBI and private laboratories that showed the presence of the steroids and Clemens' DNA on the cotton balls and syringe that had been in the beer can.

Because of Butler's objections, U.S. District Judge Reggie Walton ruled that Goldberger could not tell the jury that McNamee could have manufactured, or inadvertently created, the evidence through contamination by commingling syringes, ampules and cotton balls in one place. That is the defense theory.

Earlier Tuesday, former Yankees massage therapist Rohan Baichu testified that Clemens' body never showed any physical changes or signs of acne, a potential side effect of steroid use, during the seven years that he gave Clemens massages.

He said that after Clemens joined the Houston Astros in 2004 he saw Brian McNamee only "a few times" and that Astros strength coach Gene Coleman was the pitcher's primary trainer during those three years.

Through Baichu's testimony, Hardin attempted to distance Clemens from McNamee, who said he injected Clemens with performance-enhancing drugs in 1998, 2000 and 2001 and continued to train him through the 2007 season. Clemens is on trial for denying those allegations to Congress four years ago.

Baichu said the Astros hired him full-time in 2006, after lobbying by Clemens, and he spent that entire season living in Clemens' pool house. He said he "never" saw McNamee training Clemens that season.

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