As prison officials and reformers have stepped up efforts to reduce rape behind bars, they have looked to the supervisors who keep watch over prisoners — and prison guards — to help curb the scourge of sexual abuse.

On Thursday, federal prosecutors charged two of those supervisors, lieutenants at a federal jail in Brooklyn, and another guard with sexually abusing female inmates.

The prison where the three worked, the Metropolitan Detention Center, has long been regarded as a troubled institution in the federal Bureau of Prisons. Last year, a federal judge expressed reluctance about sending women there because the stories she had heard about the living conditions there made it sound like it was in “some third-world country.”

In the case announced on Thursday, prosecutors say one lieutenant repeatedly raped an inmate shortly before she was scheduled to be turned over to immigration authorities and deported. Another lieutenant is accused of repeatedly sexually abusing inmates assigned to clean his office, or the hallway nearby. A third man, a rank-and-file corrections officer, who was also charged on Thursday, is accused of receiving oral sex from three inmates.