2003 GMC Envoy Owner's Manual - Page 30

Rear Seat Passengers It's very important for rear seat passengers to buckle up! Accident statistics show that unbelted people in the rear seat are hurt more often in crashes than those who are wearing safety belts. Rear Seat Passenger Positions Rear passengers who aren't safety belted can be thrown out of the vehicle in a crash. And they can strike others in the vehicle who are wearing safety belts. 1-23