Transportation & Vehicle Safety Policy
 

Study

Understanding Seat Belt Use in Iowa

Currently the only passenger vehicle occupants in Iowa not required to wear a belt are adult occupants riding in the rear seat.  NHTSA reports that rear seat belts are 60% effective at reducing fatalities in motor vehicle crashes, but only about half the adults in Iowa surveyed say they typically use seat belts when riding in the back seat. The University of Iowa’s Public Policy Center, along with the UI Injury Prevention Research Center, the Iowa Social Science Research Center, and the National Advanced Driving Simulator, conducted a policy analysis to evaluate the impact of and support for implementing such a law.

Currently 28 states and the District of Columbia enforce seat belt laws for all passengers. 

Iowans as a whole do a good job of following the law,

  • 94% of front seat occupants use seat belts.
  • However, seat belt use in the rear seat is much, much less (both our survey and the safety culture survey show this).  (85% always use a belt in the front, 36% always use a belt in the back seat)
  • Many respondents said they don’t because it’s not the law

This is a problem because

  • Although frequently touted as the safest place in a vehicle, the rear seat is no longer the safest place for adults to sit
    • Few advances have been implemented to improve safety for rear seat occupants while many advanced safety systems have become standard for the front seat
    • If an adult must sit in the rear seat, it is critical they buckle up to prevent them from moving about the vehicle cabin and striking the driver or other vehicle occupants, and from potentially being ejected outside the vehicle
    • Drivers using a seat belt with a passenger in the rear seat are 2.5 times more likely to die if the rear passenger is not wearing a seat belt than if s/he is
  • Of adults who suffered fatal injuries in a motor vehicle crash from 2006-2012, when belt use was recorded
    • 53% of the drivers were using a belt
    • 60% of the front seat passengers
    • Only 17% of those known to be seated in the rear seat

Iowans do widely and strongly support the passage of this law

  • 62% of respondents said they thought Iowa law should change to require all rear seat passengers to use seat belts
  • Overall 40% of iowa residents strongly support, another 20% somewhat support passing the law

If the law was passed, it would be effective

  • Survey results also show that most adults would use seat belts in the rear seat if it was the law 80%

Sponsored by the Iowa DOT

UI researchers: Michelle Reyes and Dan McGehee