Updated

A judge assigned to Roger Clemens' perjury case issued a gag order Monday prohibiting public comments by the principles in the case that could affect the jury pool for a possible trial.

Clemens was indicted by a federal grand jury Thursday for allegedly lying to Congress. The six-count indictment accuses the seven-time Cy Young Award winner of obstructing a congressional inquiry with 15 different statements made under oath, including denials that he had ever used steroids or human growth hormone.

Clemens has denied any wrongdoing.

U.S. District Judge Reggie Walton said in the gag order that interested participants will refrain from making public comments that could have a material effect on the case.

"Further action in violation of this admonition will be confronted of the full authority of the Court," Walton wrote in the order that covers "the parties, any potential witnesses, and counsel for those parties and witnesses."

Walton has some experience with high-profile cases, presiding over the perjury and obstruction trial of Vice President Dick Cheney's former chief of staff, I. Lewis "Scooter" Libby.

No date has been set for Clemens' initial court appearance. The former pitcher faces a combined maximum sentence of 30 years in prison and a $1.5 million fine if convicted on all charges. However, under U.S. sentencing guidelines, he probably would face no more than 15 to 21 months in prison.