By the late 1990s, the flood of inmates from this new class of prisoner, coupled with a raging War on Drugs, sent the Bureau of Prisons searching for places to put them. The BOP turned to private companies to operate a new type of facility, low-security prisons designed to hold only noncitizens convicted of federal crimes. As of June 2015, these facilities—which are distinct from immigration detention centers, where people are held pending deportation—housed nearly 23,000 people.”