The incident began around 11:30 p.m. Wednesday in Southwest Philadelphia.
Police say there was a fender bender involving two vehicles, and one of the drivers left the scene.
Investigators believe that driver was DUI, and fled because he did not want to be arrested.
However, the other driver involved followed the suspected DUI driver to his home in the 6400 block of Grays Ferry Avenue, and the two get into a confrontation.
Police say the pursuer had a license to carry a gun. He unholstered the weapon and it went off.
The suspected DUI driver was shot in the wrist. He was taken to the hospital in stable condition.
Police say the pursuer handed his weapon over to officers when they arrived on the scene.
He is not facing any criminal charges.
The driver who fled the scene is charged with DUI.