"The request to open an investigation on the congressional testimony of Roger Clemens has been turned over to the FBI and will receive appropriate investigative action by the FBI's Washington field office," FBI spokeswoman Debra Weierman said Thursday.
The inquiry announcement came one day after two leaders of the House Oversight and Government Reform Committee asked Attorney General Michael Mukasey to investigate Clemens. The probe could result in charges against Clemens of perjury, making false statements or obstruction of justice. Lawmakers did not ask for a similar investigation of McNamee.
Clemens, a seven-time Cy Young Award winner, testified under oath that he never used steroids or human growth hormone. McNamee said he injected Clemens with performance-enhancers at least 16 times from 1998-01.
"We've always expected they would open an investigation," said Clemens' lead lawyer, Rusty Hardin. "They attended the Congressional hearing. So what's new?"
IRS Special Agent Jeff Novitzky, a key member of the government's prosecution in the BALCO drug cases, attended the hearing and watched from the second row.
Earl Ward, McNamee's lead lawyer, wanted to confer with his client before commenting.
Barry Bonds, a seven-time MVP, was indicted in November on perjury and obstruction of justice charges stemming from his 2003 grand jury testimony in which he denied knowingly taking illegal performance-enhancing drugs.
Clemens was first identified as taking steroids in a December report by former Senate majority leader George Mitchell, a Boston Red Sox director hired by baseball commissioner Bud Selig to examine drug use in baseball. The Mitchell Report was the first public accounting of McNamee's allegations that he injected Clemens with HGH and steroids.
Two of Clemens' former New York Yankees teammates, Andy Pettitte and Chuck Knoblauch, have both acknowledged that McNamee was correct when he said they used performance enhancers.
In a letter seeking the inquiry, the House panel cited sworn statements by Pettitte, who said Clemens had discussed HGH with him nearly a decade ago.
"We believe that his testimony in a sworn deposition on Feb. 5, 2008, and at a hearing on Feb. 13, 2008, that he never used anabolic steroids or human growth hormone, warrants further investigation," committee chairman Henry Waxman of California and ranking Republican Tom Davis of Virginia wrote.
"That testimony is directly contradicted by the sworn testimony of Brian McNamee, who testified that he personally injected Mr. Clemens with anabolic steroids and human growth hormone," the lawmakers wrote.
"Mr. Clemens's testimony is also contradicted by the sworn deposition testimony and affidavit submitted to the committee by Andrew Pettitte, a former teammate of Mr. Clemens, whose testimony and affidavit reported that Mr. Clemens had admitted to him in 1999 or 2000 that he had taken human growth hormone."
Waxman's office declined comment Thursday.
Clemens is the latest professional athlete to come under federal scrutiny for statements made about alleged use of steroids or performance-enhancing drugs. Last month, the FBI opened an investigation into whether Houston Astros shortstop Miguel Tejada lied in 2005 when he told federal authorities he never took steroids or HGH.
Former Olympic track gold medalist Marion Jones was sentenced in January to six months in prison for lying to federal investigators about taking the designer steroid "the clear."