Federal authorities have accused New York City of miscalculating employment benefits for officers of the nation’s largest police department while they were away serving in the military. Southern District U.S. Attorney Preet Bharara announced yesterday that his office has filed a class action lawsuit on behalf of current and former New York Police Department officers who have served since Sept. 11, 2001.

The lawsuit accuses the NYPD of calculating pension benefits for the soldiers solely on the base pay. It says that violates federal rules requiring the police department to factor in the probable overtime and night differential pay. The city, the NYPD and the city Police Pension Fund are named as defendants.