On Monday, January 12, 1998, near the end of his shift, Dinkheller pulled a motorist over for speeding.

A verbal confrontation ensued which escalated, causing Dinkheller to be shot and killed. The suspect was wounded in the stomach by a shot from Dinkheller's service pistol. Despite the wound, the perpetrator, Andrew Brannan, was able to kill Dinkheller and flee the scene; he was discovered the next morning hiding in a sleeping bag beneath a camouflage tarp in Laurens County, Georgia, by police, and arrested for the murder of Dinkheller.

Brannan pleaded not guilty by reason of insanity, but the jury found that the murder of Dinkheller was carried out in a torturous and cruel manner. Brannan was found guilty of murder on January 28, 2000, and was sentenced to death on January 30, 2000