"Consider the prison-phone industry"

From an article explaining how the prison system in the United States has been corporatized into profitable ventures:

The profits generated by the corrections economy have not been definitively calculated, and a comprehensive audit would be a staggering accounting task. The figure would have to include the cost of private-prison real estate, mandatory drug testing, electronic monitoring anklets, prison-factory labor, prison-farm labor, prison-phone contracts, and the service fees charged to prisoners’ families when they wire money for supplies from the prison commissary. Contracted commercial activity flows in and out of every city jail, rural prison, suburban probation office, and immigration detention center. For stakeholders in the largest peacetime carceral apparatus in the history of the world, the opportunities for profit add up. For analysts like Sommer, the system also offers a safe, government-secured investment...
Consider the prison-phone industry. For inmates, especially urban felons shipped to far-off rural sites, calls to the outside are a social lifeline and a proven method for reducing recidivism. But here, too, Wall Street has identified a high-demand, low-supply commodity. Other government contractors, be they food suppliers or dentists, collect fees paid out by the state. Prison-phone companies, and the prison-wire-transfer companies that are following their model, extract revenues directly from inmates and their families. (Fifteen dollars for a fifteen-minute phone call is not uncommon.)
As with partnership corrections, profits are largely determined by contracts, but phone and money-transfer companies sweeten the deals for their public partners with profit-sharing perks. These commissions kick back anywhere from 40 to 60 percent of revenue to the contracting government agency. According to a study by Prison Legal News, a publication of the Human Rights Defense Center, about 85 percent of non-federal jails sign up for commission-added contracts, and because commissions increase in proportion to the total contract value, cash-strapped public officials are motivated to choose the most expensive contract available. Prison Legal News found that when Louisiana put out a public request for proposals for phone services in 2001, the agency stated the wish explicitly: “The state desires that the bidder’s compensation percentages . . . be as high as possible.”