Updated

Drew Peterson's attorney is denying reports that the former police sergeant who is suspected in his wife's disappearance allegedly used department computers to run unauthorized checks on people his wife knew.

Attorney Joel Brodsky said the practice was widespread at the Bolingbrook Police Department and wrote a letter to State's Attorney James Glasgow that said charging Peterson with doing so would constitute "vindictive prosecution" because others have not been charged.

"Our investigation reveals that it was common practice of members of the Bolingbrook Police Department and employees, where people would run family members, cousins and such to see if there were any active warrants or see if there was anything on a daughter's new boyfriend," Brodsky said.

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Prosecutors are reviewing an internal police investigation to determine whether Peterson could be charged for official misconduct. The Will County State's Attorney's office would not discuss the internal investigation other than to say no charges have been filed against Peterson.

Police Lt. Ken Teppel declined to provide any details of Peterson's alleged misconduct, but ABC's "Good Morning America" reported Monday that it included Peterson's alleged use of police computers to find information on friends of his missing wife.

After 23-year-old Stacy Peterson disappeared in late October, authorities have named her 53-year-old husband a suspect in what they have said is a potential homicide. Prosecutors also are reviewing the death of Peterson's third wife, Kathleen Savio, and have said the drowning, deemed accidental at the time, may have been a homicide staged to look that way. Peterson has not been named a suspect in her death.

Brodsky said Monday that Peterson denies using police computers or databases to gather information about his wife's family or friends or in any unauthorized way. Teppel disputed Brodsky's contention that the practice is widespread and unchecked.

The department could lose the state certification that allows it to run names if it does so in the way Brodsky described, Teppel said.

"Guys have been fired over this," Teppel said. "The last one (in March 2006) was a dispatcher who was terminated for handing that information over to a repo man."