Investigation Into Oklahoma Prison Gang, Drug Trafficking Ends With 125 Convictions

A five-year investigation into an Oklahoma-based prison gang uncovered a multi-state drug trafficking operation headed up by an inmate inside a maximum-security cell.  

Multiple agencies including the Federal Bureau of Investigation, Oklahoma City Police, the Internal Revenue Service, and the U.S. Attorney’s Office in Oklahoma City.  

The investigation ended with 125 criminal convictions involving 17 state inmates who coordinated drug deals, couriers, suppliers, and others.  

Law enforcement seized more than 525 pounds of methamphetamine and heroin, 212 firearms, and almost $600,000 in drug proceeds during the investigation, according to U.S. Attorney Robert Troester.  

“This gang not only moved a lot of drugs, but was particularly violent,” Troester said. Two attorneys in his office received threats from gang members during the investigation. “It did not deter them in the slightest.”  

“This very widespread trafficking organization did their work from prison cells in Oklahoma prisons and county jails through the use of contraband cell phones,” Troester said.  

David Postelle was the lead coordinator of IMG’s operations while he served multiple life sentences at the Oklahoma State Penitentiary in McAlester. Postelle a codefendant in the quadruple murder case the landed his relative, Gilbert Postelle, on death row.  

Postelle used a small contraband cell phone to coordinate drug purchases, deals, and more, all from inside his cell.  

“A small number of people with a cell phone can organize and move this large organization and keep the drugs, guns, and criminal conduct flowing,” Troester said.  

Related: Oklahoma Executes Convicted Murderer Gilbert Postelle In McAlester 

The investigation targeted various parts of the drug trafficking operation’s supply chain, from suppliers to couriers to “enforcers”, according to a federal indictment.  

At least one prison employee helped keep the operation functioning inside the maximum-security facility.  

Andrew Pranger worked at the state penitentiary and was paid “thousands” to smuggle in contraband cell phones and warn the inmates of cell searches. He was sentenced to 18 months in federal prison followed by two years of probation.  

Troester said 113 of the convictions resulted in 1,350 combined years in prison sentences.  

“I would love to think they’ve learned their lesson and stop, but I anticipate they will continue to look for ways to continue their criminal enterprise,” he said.