A federal judge refused to dismiss terrorism charges against Jose Padilla over claims that the alleged Al Qaeda operative was tortured in U.S. military custody, removing one of the last major obstacles to the start of his trial next week.

U.S. District Judge Marcia Cooke stressed in a 12-page order filed late Monday that she was not passing judgment on the torture allegations. Rather, she said the effort to dismiss the case for "outrageous government conduct" was faulty on legal grounds.

Padilla's lawyers claim that during the 3 1/2 years Padilla was held as an "enemy combatant" at a Navy brig he was routinely subjected to harsh treatment and torture.

He claimed that he was forced to stand in painful stress positions, given LSD or some other drug as a "truth serum," subjected to loud noises and noxious odors, and forced to endure sleep deprivation, extreme heat and cold and harsh lights.

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The Pentagon and Justice Department have repeatedly denied those claims. Officials with the brig in Charleston, S.C., said during earlier testimony before Cooke that Padilla, a 36-year-old U.S. citizen and Muslim convert, was not mistreated, though they acknowledged occasional removal of the mattress in his cell and of his copy of the Koran.

Padilla's four lawyers did not immediately respond to e-mail messages seeking comment Tuesday on the ruling. Prosecutors also did not immediately return a telephone call.

Padilla and his co-defendants, Adham Amin Hassoun and Kifah Wael Jayyousi, are scheduled for trial starting next Monday.

The three are charged with conspiracy and terrorism material support for allegedly being part of a North American support network for Islamic extremist groups worldwide. Each could face life in prison if convicted.

In her ruling, Cooke said the dismissal motion wasn't backed up by case law and failed on legal grounds because prosecutors aren't using any evidence collected during Padilla's time in the brig.

To rule otherwise would "effectively provide a defendant with amnesty for any uncharged crime so long as the government violated the defendant's due process rights at some prior point," she wrote.

She warned, however, that the issue could return should prosecutors decide to use evidence from Padilla's interrogations.

Cooke had ruled earlier that Padilla was competent to stand trial despite conclusions from defense mental health experts that he was suffering from post-traumatic stress disorder stemming from his years in military custody.

"The government is breathing a big sigh of relief," said David O. Markus, a prominent Miami defense lawyer not involved in the case. "The last thing it wanted were these allegations aired in open court."

Padilla was initially arrested in 2002 on suspicion of an Al Qaeda plot to detonate a radioactive "dirty bomb" in a U.S. city, but that charge is not part of the Miami criminal case. Prosecutors claim that Padilla filled out a form in 2000 to join an Al Qaeda training camp in Afghanistan.

Earlier Monday, Cooke agreed to give Padilla's defense lawyers greater power to reject potential jurors in an effort to reduce bias from the intense media coverage.

The defense will get 36 peremptory challenges, more than triple the number suggested by federal prosecutors, and prosecutors will get 30. In any criminal case, both sides are allowed an unlimited number of challenges to jurors for "cause" such as obvious partiality. Peremptory challenges allow lawyers to remove jurors without giving a reason; normally the defense gets 10 and prosecutors six.

Cooke said she would tell jurors to be prepared for the case to last until Sept. 1.