Benton County Prosecutor Van Stone said Tuesday he's filing the charge against Coleman Brackney in the death of James Ahern.
Brackney shot Ahern six times on Jan. 20 after Ahern led the officer on a high speed chase.
Brackney has said he fired the first five shots because he thought Ahern was trying to attack him with his car -- then fired a sixth shot from behind the car when the car's back-up lights came on.
Prosecutors say Brackney's dash camera video shows the car's reverse lights did not come on.
Brackney was fired Tuesday after being on paid leave since the shooting.
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