A U.S. judge rejected motions to dismiss charges against the main defendants in the BALCO steroid scandal Tuesday but ordered hearings on whether the government acted properly in the investigation.

Victor Conte, head of the BALCO lab south of San Francisco, had asked the court to dismiss charges against him on grounds of "outrageous government conduct" and other violations.

"Defendants have not presented a sufficient factual basis to warrant an evidentiary hearing on this motion, given the 'extremely high standard' of outrageous conduct," U.S. District Court Judge Susan Illston wrote in her decision.

Conte, Greg Anderson -- the personal trainer of major league baseball (MLB)'s Barry Bonds -- and two others are charged with distributing steroids in a scandal that has tarred top names in global sport.

The defendants also said the warrants in the case were based on an out-of-date tip from an informant but Illston rejected that argument.

"The court finds that the warrants were not stale, given the evidence present in the affidavits that spanned many years until May 2003," she wrote in her order.

She did side with the defendants in allowing a hearing on whether law enforcement agents gave Conte a copy of their search warrant before a September 2003 search of BALCO.

"The court grants defendant's request for an evidentiary hearing on this matter, because there is a material discrepancy between the government and the defense regarding whether the warrant was provided to the defendant," she wrote.

Illston allowed a hearing on whether investigators read defendants their Miranda rights -- in which law enforcement officials taking someone into custody must inform them that they have the right to remain silent.

"All parties agree that the defendants were subjected to interrogation and were not provided with Miranda warnings," Illston wrote.

"Thus the central question for the Court is whether the defendants were in custody at the time of the interrogations, and the facts which will determine the answer to this question are in substantial dispute."

The dispute over information the often talkative Conte told investigators has lost some of its urgency this month.

In an article and television interview earlier in December, Conte admitted distributing steroids to top athletes, and said he devised a doping program for Olympic champion Marion Jones. Jones denies the allegations and has sued Conte.

The judge's order also cited an affidavit that said during the September 2003 search Conte told investigators he gave Anderson steroids for professional baseball players.

The lawyer for Bonds said earlier this month that the San Francisco Giants slugger took creams and oils that could have contained steroids but did so unknowingly out of blind faith in Anderson, his trainer and best friend.

Illston set a January 31 date for the evidentiary hearings. The BALCO trial could begin in March.

Editor: Wing