Capt. Greg Jackson of the Camden County Sheriff's Office said authorities found Fairley Cisco, 67, dead at his St. Marys home Thursday morning after family members called 911.
Jackson said Cisco was in bed with a television on in the room. He gave no other details.
The Georgia Bureau of Investigation planned an autopsy Friday.
Cisco's attorney, Alex Zipperer, said Cisco was in poor health from several medical conditions.
Federal prosecutors charged Cisco and four others last year with cheating customers out of millions of dollars by rigging gas pumps at three service stations Cisco owned in Camden County.
Cisco had been scheduled to stand trial May 11.