Incarceration rates are beginning to fall, but big, for-profit prison companies have a growing line of business: immigrant detention.

Expand chart Data: USASpending.gov; Chart: Andrew Witherspoon/Axios

By the numbers: As of November 2017, 71% of detained immigrants were being held in private detention facilities, according to government data obtained by the National Immigrant Justice Center.

Since Trump became president, ICE has awarded more than $480 million in federal funds to GEO Group and more than $331 million to CoreCivic, according to USA Spending.

It's a similar situation to the late 1980s and early 1990s, when all levels of government began struggling to handle the surge in prison populations and turned to private prison companies to help, Brennan Center for Justice Program Director Inimai Chettiar told Axios.

The government is "rapidly increasing immigration detention, and outsourcing it to the private sector."

Between the lines: These privately run detention centers often hire fewer staff members, require less training of them or don't implement programming for detainees, Randy Capps, director of research for U.S. programs at the Migration Policy Institute, told Axios. Some have even been sued for imposing forced labor on immigrants.

"When you have kind of weak standards and you have a for-profit motive, you wind up with understaffing and you wind up with lack of services and activities," Capps said. "That's where you get to health problems, and you probably have mental health problems, too."

A spokesperson from CoreCivic, however, said this is not the case. They said detention centers are held to strict staffing standards by ICE and at least one of CoreCivic’s family facilities provides migrants amenities such as gyms, parks, a playroom and a library.

The other side: If private prisons did not hold immigrants, they would likely be sent to local jails, which often struggle to meet the federal government's detention standards, according to a GEO Group spokesperson. Private companies are also more able to adapt to seasonal trends of unauthorized immigration, adds a CoreCivic spokesperson.

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