Last week, the U.S. Department of Justice announced that it would phase out its use of private prisons. While significant, the move will not put an end to the booming immigrant detention industry. Private prison companies will continue to receive millions in government contracts to detain unauthorized immigrants.

Even though private prison companies play a central role in the government’s immigration strategy, the financial dealings between the two are often opaque. In his piece for the Washington Post, reporter Chico Harlan sheds light on one of these secretive arrangements, detailing a $1 billion deal between the Obama Administration and Corrections Corporation of America, also known as CCA, the largest private prison company in the country.

Under the deal, CCA was responsible for building and maintaining a large immigrant detention facility for women and children in South Texas; in an unusual arrangement, CCA is guaranteed payment for being at capacity regardless of how full the facility actually is.

A few highlights from our conversation:

Private prison companies are very involved in the immigrant detention industry.

Harlan: GEO and CCA are the two largest prison companies in the US. They're also hugely in the immigration detention game. They do disclose information. I just think that people tend not to follow it too closely. There are only four analysts that even cover CCA. Despite that, they are playing this enormous role in holding people who both commit crimes and who enter the country illegally or without a visa. They're worth looking at.

Harlan uncovered the deal by closely reading quarterly financial reports and looking for irregularities.

Harlan: The whole reason I found out that CCA was entitled to this guaranteed money--basically profit insurance as you might call it--was because they released something called supplemental financial information every quarter. You scroll down, and it has a little category where they show all of their facilities and then something called the compensated occupancy percentage, which basically just shows of all the amount of money we could have made per bed, here's how much we actually made. It's kind of like a proxy for how full the place was. You look at the south Texas place, and it said 100 percent. And that didn't make sense. I had just been there. I knew that it wasn't 100 percent full. I went back to the previous quarter and the previous quarter, it was 100 percent every month. This company doesn't give out much information on a per facility basis. That's one way that they really do guard against giving clues about how they are paid. And yet, they gave just one little clue that I was then able to take to other people who are involved in the deal and say, "I think I'm onto something here." And gradually that turned into confirmations.

Even when reporting on the financial aspects of the immigrant detention centers, it’s still critical do ‘shoe-leather’ reporting.

Harlan: I talked to three women in interviews that were coordinated by ICE. I had to give them their A-numbers, which is almost like akin to a prisoner number. I did not think that it was actually going to work. I showed up at this facility one morning with a translator. I was assuming that the interviews would be limited in time or would be minded by somebody from the government. Instead, they just opened the room for me, and one by one these women walked in, sometimes with their kids, and talked for hours and hours. Their stories were unbelievable. They'd been in their own home countries just a few weeks earlier and in one instance, it was a threat that was so urgent from a gang member in El Salvador that the woman was out of the country 24 hours later. Her whole life was overturned.

The public debate around immigration contrasts with what is actually happening on the ground.

Harlan: I think immigration is an irresistible subject, even though I'm somewhat new to it. As you look into it, I don't think there's anything in America that is more discussed, that brings out more opinion, but where the gulf between what's actually happening and what people believe is happening is different. Just the most glaring example is the fact that the number of undocumented people in this country is dropping and has been dropping for the last few years. This is after decades of increase. You would never think that based on the rhetoric.

Listen to this podcast on iTunes, SoundCloud or Stitcher. For more, read Harlan's piece, Inside the Administration's $1 Billion Deal to Detain Central American Asylum Seekers.