Adam Elggren, an assistant U.S. attorney, also alleged a videotape at a restaurant where Laura Bustamante worked a second job as a waitress shows her stealing items from a co-worker's purse.
The information was presented to Magistrate David Nuffer at a detention hearing for Bustamante, 34, and her co-defendant, John Johnstun, 44.
Bustamante's lawyer, Henri Sisneros, said that his client has led a "completely law-abiding life" and the recent charges against her are the first time she has been accused of a crime. He said Bustamante is separated from her husband, with whom she shares joint custody of their three children.
Nuffer ordered Bustamante held in jail until another hearing next Monday. The judge said he is leaning toward having Bustamante wear an electronic monitoring device and allowing her to live with her mother in Taylorsville.
Also at today's hearing, Nuffer ordered that Johnston, who is Bustamante's boyfriend, be detained until the case is resolved. The magistrate said Johnstun, a 44-year-old motorcycle mechanic, is a flight risk.
Elggren said Johnstun has three drug-related convictions in state court and a history of failing to show up for hearings.
Johnstun, who lives with Bustamante in Midvale, is accused of one count of destruction of records for allegedly helping destroy evidence in the case. Bustamante is charged with computer fraud, aggravated identity theft and destruction of records.
Bustamante was fired earlier this year from her job as an eligibility specialist after DWS investigated an anonymous tip that she was committing identity theft. Charges filed by the U.S. Attorney's Office allege that her offenses began in September 2007.
Two other people - Michelle Chapman, 29, and Joshua Smith, 32, both of Murray - have been charged with access device fraud and aggravated identity theft in the case. They are being held in jail pending a Tuesday detention hearing.
