Sean Street, 39, pleaded guilty to aggravated identity theft, a federal crime punishable by a mandatory two-year prison term.
Street was fired from the department in 2012 after his role in the tax fraud crime was uncovered.
Federal agents tracking fraudulent income tax filings discovered a list containing 108 names with personal identity information such as Social Security numbers and dates of birth.
The list included people who had come into contact with Street between December 2011 and February 2012. Law enforcement officers routinely collect names, dates of birth, addresses and Social Security information from suspects, witnesses and victims.
First Assistant U.S. Attorney James Durham said the total tax fraud amounted to $414,000, although the discovery of the scheme saved taxpayers all but about $70,000.
Street was told he would get $1,500 for each name but he never received payment, Durham said.
According to then-Sheriff Ronnie Strength, an internal investigation was launched. The names on the list were run through a computer, and Street was discovered to be the common factor among all of the people.
Street admitted to federal agents that he supplied those names to another person involved in a tax fraud conspiracy.
Street had been on the force for four years.