Deputies were dispatched on a call about a fight. One arrived to the scene and later fired his gun in what he describes as self defense.
"He did not have a choice. It was either get hurt or do what he had to do," Sheriff Chuck Phillips of the Jackson County Sheriff's Office said.
Sheriff Chuck Phillips defended his deputy's actions.
When his deputy arrived to the home on County Road 60, he said he saw an 18-year-old on top of a car with a 3 foot board in his hands.
The teen, Alex Davis, was apparently trying to shatter the windows. The deputy tased the young man twice, but that didn't work.
"If a taser won't bring him down and he's coming at you and he's as close to me and you with a board in his hands, what do you do? I'm not going to let him hit me with a board in the head," Sheriff Phillips said.
Davis was shot and killed.
Authorities said he was a student at Pisgah High School and that they had encounters with him in the past.
The NBC affiliate in Huntsville, WAFF 48 News, spoke with the young man's bus driver. Melissa Morgan Rosalie said he was "very friendly" and a "good friend."
"Always greeted me with a big smile and told me he loved me," she said.
Neighbors learning about the shooting are questioning why someone had to die.
"Why didn't he shoot him in the leg? To be honest, that's what I thought. If I had known the person out there, that's what I would've hoped he would have done to have stopped him," Margaret Rice, a neighbor said.
Before the shooting, the sheriff said the teen beat a man with a sledgehammer.
While Gary Gibbons didn't want to speak on camera, he said he didn't know Davis. He only knew his friend who was with him who offered a hand in fixing the man's truck.
Gibbons remembered the two men were arguing about a girl and he wanted them to leave. He still isn't sure why he was attacked, but said the young man was shot twice.
"I feel sorry for the boy and the boy's family. That's about all I can say," Rice said.
The Alabama Law Enforcement Agency or ALEA has taken over the investigation.
The deputy involved will also go through counseling. That and paid administrative leave are standard protocol, according to the sheriff.