Sgt. Kevin Rascher turns his cruiser onto the gravel in South Dakota Indian Country, guns the engine, and races toward an emergency call 20 miles away. The Chevy Tahoe bounces down the back road at 95 mph, sirens howling, past gutted cars and broken beer bottles. Another drinker. Another fight. Rascher’s shift on the Pine Ridge Indian Reservation began two hours ago, and the tribal highway officer has already arrested four Indians on alcohol charges.