The Sheriff's Department says it got a call about a man who was acting suicidal. When a deputy arrived at the scene Davis approached him with a box cutter.
Authorities say Davis had already cut himself several times. They also say he rushed the deputy and threatened to kill him.
The deputy said he unsuccessfully tried to fire a shot at Davis and that's when Davis jumped on him. They said another deputy arrived, saw the struggle and shot Davis.
Both deputies are on administrative leave with pay.
Davis has been in trouble with the law in the past. He was convicted of a felony injury in 1996 and got a one-year sentence.