ben johnson , who has been on the force four years , was answering reports of a drunk woman inside deluxe nails at a strip mall in red rock on tuesday .
video taken on his cash cam and by a person in a nearby shop appear to show a different story .
police in red rock , texas , are into this video to see if officer ben johnson used excessive force when taking down viviana keith , 27 , who was arrested amid reports of drunken behavior and dui .