dietrich evans was arrested on suspicion of shooting kay hafford in the head in a road rage attack during rush-hour .
the brave church singer they discovered the gun used to shoot through hafford 's window and a car matching the description of the shooter 's .
evans , who is still recovering , had been trying to get on the freeway in houston when she honked at him , prompting the man to fire on the passenger window of her dodge avenger that evans said the pair had an angry exchange and the driver then began taunting her .