The U.S. attorney's office is suing the city's Department of Transportation over claims of racial discrimination.
According to a lawsuit filed Wednesday by Preet Bharara, the agency racially discriminated against and retaliated against minority employees in the Fleet Services division.
Incidents mentioned in the suit date back to 2007.
In one, an executive director allegedly requested a supervisor be demoted because he was black.
It also alleges that same person used racial epithets to describe two other black employees.
The DOT said in a statement it's working with the Justice Department on a resolution to the allegations made in the suit, and has made changes.