The stop ended in the shooting death of 17-year-old Hunter Brittain.
When Pope County Prosecuting Attorney Jeff Phillips, acting as the special prosecutor in this case, announced the charge during a news conference that included supporters of Brittain's family, several of them cheered.
Phillips kept a straight face, read the complaint and declined to answer any questions.
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Davis surrendered to police around noon and will remain at an "undisclosed county jail" before his bond hearing Monday, state authorities said.
"This defendant will be treated as anyone else," Phillips said. "This case is going to proceed, emotions will continue to run high."
Brittain and friend Jordan King had been up late fixing the transmission of the victim's GMC truck before going for a test drive at 3 a.m. on State Highway 89 in Cabot, about 25 miles northeast of downtown Little Rock, according to a warrant for Davis' arrest.
As Davis pulled them over, the truck did not slip into park, prompting Brittain to jump out and reach into the GMC's bed, the complaint said. Davis allegedly told investigators he didn't see what was in Brittain's hands when he fired one fatal shot into the teen's neck, according to the arrest affidavit.
"Davis says as he observed the bullet strike Brittain, a container came from Brittain's hands that originated from the bed of the truck," according to the complaint. "The container landed on the ground."
The victim's family said that was a bottle of antifreeze that Brittain intended to use to block his truck from rolling backward toward Davis' squad car.
"King said he never heard anyone say show me your hands or words similar to that before hearing the gun shot," the complaint said. "No evidence of firearms were located in or around Brittain's truck."
Civil rights attorneys Ben Crump and Devon Jacob, who represent the victim's family, welcomed the action against Davis.
“These charges are just the first step in the pursuit of justice for Hunter Brittain whose life was tragically ended by this unjustified use of deadly force," the attorneys said in a statement. "This is the latest example of law enforcement shooting first and asking questions later."
Davis' lawyer could not be immediately reached for comment on Friday.