HOUSTON -- A man found guilty of killing a Memorial High School student during a spring break party was sentenced to prison, KPRC Local 2 reported Friday.

On Thursday, a Harris County jury found Robert Odom Jr. guilty of manslaughter in Allison Aubrecht's death, after 25 minutes of deliberation.

He was sentenced to the maximum of 20 years in prison on Friday. Jurors took about three hours to decide the punishment.

Aubrecht, 17, was shot at Odom's home in the 6500 block of Westview Drive on March 15, 2009. She was one of about eight people attending a party at the house.

Houston police said Aubrecht was shot in the back of the head when Odom, 21, pulled out a gun, pointed it around the room, put it to Aubrecht's head and pulled the trigger.

Investigators said Odom thought the gun was not loaded. He admitted that he was high on marijuana and beer at the time.

Odom was facing two to 20 years in prison. Defense attorneys asked for probation while prosecutors wanted the maximum punishment.

"I was just thrilled that they gave him the max amount of punishment for the charge he received. However, Ali's gone forever. He took her life. Personally, I don't think he should have his life left," said Loraine Aubrecht, Allison's mother.

Prosecutors said they asked for the maximum because Odom was so reckless. They also hope his sentence serves as a warning for spring breakers.

"We just believe society has spoken -- that they would not tolerate alcohol, drugs and guns together," said Jim Leitner, an assistant Harris County district attorney.

Aubrecht's mother said her daughter was a joy to everyone and her family still struggles with their loss.

"The most joyful, happy girl -- always smiling. No matter who you were or where you came from, she made you feel like a million dollars," she said.

Allison Aubrecht was a senior at Memorial High School, preparing to attend the University of Texas at San Antonio.