In the end, a former Georgia Tech employee who stole $316,000 with university credit cards stood mute before a federal judge as she was sentenced to 32 months in prison.

Donna Renee Gamble of Marietta was too embarrassed to talk in open court Tuesday or to even ask friends to come and speak on her behalf, said her defense attorney, Jimmy Berry. He suggested she was struck by some sort of “obsession” over a five-year period that caused her to buy things like a jet ski, a popcorn machine, a wide-screen TV, robotic vacuums, a treadmill and Auburn University football tickets.

“You just never know why,” Berry said after the brief hearing. “People get away with things and they mushroom. She did it a few times, there were no checks and balances at the school and it took off from there.

“The things they bought were for the betterment of the family,” Berry said of the 43-year-old mother of two daughters. “I guess it was something like that, she rationalized.”

U.S. District Court Judge Jack Camp cited the “frivolous nature” of her purchases before sentencing. Gamble, who worked in the Parker H. Petit Institute of Bioengineering and Bioscience, also was ordered to repay $316,000. Authorities have seized many of the items she bought with grant-funding from the National Science Foundation. The cards, called “p-cards,” are issued for state employees to buy work-related goods and services.

“I don’t see why you didn’t see it was wrong to steal $316,000 from the Georgia Institute of Technology,” Camp said before pronouncing sentence.

Neither Gamble, nor her husband Mickey, who sat with her before the hearing, spoke afterwards.

Federal prosecutor Russell Phillips called her actions “incredibly greedy, selfish and wasteful.” Gamble purchased a total of 3,800 items with 2,000 separate purchases, many of them from her computer at work, he said.

“It takes a lot of time to buy 3,800 items in 2,000 transactions,” Phillips said. “It’s much worse than if she wrote a single check for $316,000.

Gamble’s spending spree went unnoticed until August 2007 when a tipster called Georgia Tech auditors. Results of an investigation of the p-card program at the state’s 35 public colleges and universities found 18 cases of fraud, according to a report released in January by the University System of Georgia. Gamble was the only federal prosecution so far.

The state has indicted four people in other cases of alleged p-card fraud, said Russ Willard of the Attorney General’s office, noting one had pleaded guilty. He said other cases are being investigated.

Another former Tech employee, Michelle Harris, a former program coordinator in the school’s College of Management, was indicted this year and charged with using $173,000 in school money for personal expenses, including a diamond ring, laptop computers, digital cameras and making several debt payments.

Brad Douglas, the commissioner of the Department of Administrative Services, said the number of cards had been reduced from about 20,000 to 15,000. The program had grown from a small purchasing program into a more then $300 million in annual charges.