Walden, 48, apparently opened the driver’s door “and attempted to grab his sunglasses from the ground while keeping his foot on the brake,” at the Piedmont Driving Club, an Atlanta police spokeswoman told the Atlanta Journal-Constitution. “At some point, the vehicle rolled back, possibly from his foot coming off the brake, pinning him against the pillar.”

Club members freed Walden and administered first aid until paramedics arrived, according to the paper. He reportedly died of blunt force injury to the chest.

Walden worked for his father at Macon, Ga.-based Capricorn Records, home to Southern rock mainstays including The Allman Brothers Band and Marshall Tucker Band, before becoming an attorney and relocating to Atlanta to practice law, according to the AJC.

Phil Walden Sr. died of cancer in 2006.