MIAMI — A federal judge sentenced Jose Padilla to 17 years in prison for terrorism conspiracy, rejecting the life sentence urged by prosecutors because of the harsh treatment Padilla received while in military custody.

With credit for time he has served in federal custody since his January 2006 transfer from a Navy brig in South Carolina, the 37-year-old Padilla could be free before he turns 50.

In sentencing Padilla and two co-defendants, U.S. District Judge Marcia Cooke deemed the terms set in federal sentencing guidelines of 30 years to life disproportionately severe to their crimes. She cited the life terms meted out to Oklahoma City bomber Terry Nichols and to would-be hijacker Zacarias Moussaoui in rejecting the same for Padilla, pointing out that there were neither victims of his crimes nor any damage done to American security or interests.

Padilla’s mother, Estela Ortega-Lebron, celebrated the unexpectedly lenient sentence, proclaiming “Hallelujah!” outside the courthouse and saying it proved her son wasn’t the dangerous terrorist alleged by the government. Judge Cooke also cut the time given to Padilla’s co-defendants, computer programmer Adham Amin Hassoun of Fort Lauderdale, Fla., and former San Diego schools administrator Kifah Wael Jayyousi from the 30-to-life provided for in sentencing guidelines.

Hassoun, who recruited Padilla to join the fight to defend Muslims under siege in places such as Bosnia and Chechnya, drew 15 years and eight months while Jayyousi received 12 years and eight months.

Jayyousi’s attorney, William Swor, said he appreciated Judge Cooke’s recognition that Jayyousi was the least culpable in the alleged conspiracy to murder, maim, or kidnap persons overseas and to provide material support to terrorist groups. But he condemned the government’s case brought against the three defendants.

“The government hasn’t made America any safer nor promoted the rule of law. It has just made America less free,” Swor said, noting his client’s participation in the alleged conspiracy involved writing a newsletter and speaking his mind about the abuse of Muslims in foreign conflicts.

Assistant U.S. Attorney John Shipley informed Judge Cooke that the government objected to the sentences as too lenient and would appeal.

Judge Cooke told the court she rejected the government’s position that she shouldn’t take into consideration the three-and-a-half years Padilla spent in military custody without charges after being declared an enemy combatant.

He was subjected to “enhanced interrogation” that his attorneys said amounted to torture and was never charged with the crime the government originally alleged when he was arrested in May 2002, that he had been plotting with other Al Qaeda suspects to detonate a radioactive dirty bomb in an American city.

The judge ruled that since Padilla had been held in solitary confinement without a mattress, clock, books, human contact, or legal representation, his treatment warranted a reduced sentence.