Oklahoma allowed private companies to employ incarcerated workers for outside calling campaigns, including work that ultimately reached a presidential campaign.

When Oklahoma inmate Steve Wilbanks spoke to a reporter by phone in late July, it had been six weeks since he worked in a prison call center, placing calls on behalf of insurance companies attempting to poach business from competitors and making political calls as primary elections were underway across the country. “I had good numbers,” Wilbanks, who is incarcerated at the James Crabtree Correctional Center in Helena, said. “I was a producer.” Wilbanks was one of four inmates who spoke with reporters about the call center work. Contracts obtained via an open records request confirm that a company called...