According to newly released police video, a Texas trooper threatened Sandra Bland with a Taser when he ordered her out of her vehicle during a traffic stop on July 10, three days before she was found dead in a county jail.

Bland — a 28-year old African American woman — was stopped for failing to signal while changing lanes, but the routine traffic stop turned confrontational after the officer, Brian Encinia, ordered Bland to put out her cigarette.