Cadillac 2002 DeVille Owner's Manual page 35

The side impact air bags for the rear seat outboard
passenger positions are in the sides of the rear seatback
closest to the doors.
CAUTION:
If something is between an occupant and an air
bag, the bag might not inflate properly or it
might force the object into that person causing
severe injury or even death. The path of an
inflating air bag must be kept clear. Don't put
anything between an occupant and an air bag,
and don't attach or put anything on the steering
wheel hub or on or near any other air bag
covering. Don't let seat covers block the inflation
path of a side impact air bag.
1-29