>> Read more trending news
Washington was driving down I-285 with his wife, Martin and another family member after picking his wife up from work around 3 a.m.
Martin was sitting behind Washington, playing with a gun he recently got, when he fired a shot through the seat, police said, according to WSB. Washington was hit in the upper body.
"Based on his interview, as well as the interviews of the other people in the car, and as well as evidence in the vehicle, they were able to determine that this was accidental," DeKalb County Police Department spokeswoman Shiera Campbell told WSB. "This was not an intentional shooting."
Washington was taken to a local hospital in critical condition, police said. According to WSB, his wife, who was in the front passenger seat, was also taken to a hospital after she had a panic attack.
Police have charged Martin with involuntary manslaughter.