Alleged Al Qaeda operative Jose Padilla has mild anxiety and personality disorders but is mentally able to stand trial, a prison psychologist said Monday in testimony that contradicted two defense experts.

Rodolfo Buigas, the supervisory forensic psychologist at the federal detention center in downtown Miami, rejected the defense experts' diagnosis that Padilla cannot help with his defense because he suffers from post-traumatic stress disorder as a result of his treatment in U.S. military custody. Buigas said Padilla's anxiety and anti-social personality are minor problems.

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"The nature and severity of the symptoms were not sufficient to interfere with some basic capabilities," Buigas told federal Judge Marcia Cooke, who must decide Padilla's mental fitness.

The question is crucial in determining whether Padilla, 36, and two co-defendants will stand trial in April on charges of being part of a North American terror support cell that provided finances, recruits and supplies to Islamic extremists around the world. All three face up to life in prison if convicted.

Padilla, a U.S. citizen and former gang member, has been held in isolation during his 3 1/2 years in military confinement. He was arrested in May 2002 at Chicago's O'Hare International Airport after a trip to Pakistan and Afghanistan. Officials initially claimed he was on a mission to detonate a radioactive "dirty bomb" in a major U.S. city, but the dirty bomb allegations are not part of the Miami case.

Padilla was designated an "enemy combatant" and imprisoned by the military without criminal charges.

Padilla has claimed in court filings that he was tortured at the Navy brig in Charleston, South Carolina, which officials have denied. Cooke ordered officials from the brig to appear at the hearing Monday.

Buigas testified that the affidavit Padilla signed alleging mistreatment at the brig was evidence of his mental competence.

One of Padilla's lawyers, Andrew Patel, testified that he has never been able to get meaningful information from his client. Patel also said that Padilla seems to think his lawyers are part of a government plot against him.

"He has expounded the belief that we are part of the continuing interrogation," Patel said.