The states where private prisons are thriving

Since the first private prison opened in 1984 in Tennessee, for-profit incarceration has ballooned into a $5 billion industry. In 2017, 121,420 people — about 8% of the U.S. prison population — were housed in private facilities, but the share is much higher in some states.

Why it matters: Private prisons tend to hire fewer guards than state and federal prisons and often are more dangerous.

• A spokesperson for private prison firm GEO Group told Axios the company's services comply with federal standards as well as third-party accreditors’ guidelines.
• Still, private institutions had 28% more inmate-on-inmate assaults than their public counterparts, according to a 2016 Justice Department report.

By the numbers:

• The 2017 prison population is slightly (4%) smaller than it was in 2015.
• The states with the highest share of inmates in private prisons were Montana (38.1%) and Hawaii (28.5%).
• Texas and Florida together housed 24,404 inmates in private prisons.
• A population of zero in the above chart indicates no prisoners were held in private prisons at the end of the year in 2017. But those states could still have such facilities, per the Bureau of Justice Statistics.

The bottom line: The private prison industry has boomed under the Trump administration. In November 2016, President Obama pushed an executive order to end the Justice Department's reliance on private facilities, but President Trump rescinded the order once he took office.

• Since then, the stocks of the two biggest private prison companies have surged: CoreCivic is up 56% to $22.78 and GEO Group is up 46% to $23.02.

Go deeper: This story was originally published in 2017 and has been updated with recent data.

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