Jackson, 36, was drafted by the Vikings in the second round of the 2006 NFL Draft and played 10 years in the NFL, including five years in Minnesota where he went 10-10 in 20 starts while throwing for 39 touchdowns and 35 interceptions.
Jackson retired at age 32 following the 2015 season.
Jackson died in a car accident on Sunday night, according to Ian Rapoport of the NFL Network. He was 36 years old. The car accident happened in Alabama, where he grew up. Jackson was traveling on Pike Road near Antioch Lane, about 7 miles south of Montgomery, when his 2012 Chevrolet Camaro left the roadway, struck a tree and overturned, Carswell said. Jackson was taken to a hospital where he was later pronounced dead.