A military jury sentenced a U.S. Coast Guard cadet to prison and kicked him out of the service Wednesday for extorting a classmate for sexual favors.

Cadet Webster M. Smith, the first student court-martialed in the academy's 130-year history, received a six month sentence.

He was acquitted of rape, but faced time in prison for extortion, sodomy, indecent assault and other charges.

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Defense attorneys for Smith, 23, of Houston asked jurors to spare him jail time, saying the stigma of his conviction will follow him forever. He will not graduate from the Coast Guard Academy and must register as a sex offender in Texas.

"I am ashamed to have been the first cadet to have been court-martialed," Smith told jurors, "but I am proud of my decision to fight for my career and freedom."

Prosecutors asked jurors to send Smith to prison for three years, saying he had disgraced the Coast Guard and betrayed the nation's trust.

"You get to tell your fellow Coast Guardsmen, with everyone looking at our service and our academy, whether or not that's a big deal," said Cmdr. Ronald Bald, the prosecutor.

The case involved four female cadets, but the jury acquitted him of sexual misconduct charges, including rape, involving three of them. The primary charges on which he was convicted stemmed from a series of sexual encounters with a classmate in her dorm room.

The classmate said she was too afraid to protest because she feared Smith would reveal a secret that could have jeopardized her Coast Guard career. Smith, who testified in his own defense, said the sex was consensual.

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