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Mandatory Seatbelt Laws and Traffic Fatalities: A Reassessment

Author

Listed:
  • Anderson, D. Mark

    (Montana State University)

  • Liang, Yang

    (San Diego State University)

  • Sabia, Joseph J.

    (San Diego State University)

Abstract

Using data from the Fatality Analysis Reporting System for the period 1983-1997, Cohen and Einav (Review of Economics and Statistics 2003; 85(4): 828–843) found that mandatory seatbelt laws were associated with a 4 to 6 percent reduction in traffic fatalities among motor vehicle occupants. After successfully replicating their two-way fixed effects estimates, we (1) add 22 years of data (1998-2019) to capture additional seatbelt policy variation and observe a longer post-treatment period, (2) employ the interaction-weighted estimator proposed by Sun and Abraham (2021) to address potential bias due to heterogeneous and dynamic treatment effects, and (3) estimate event-study models to investigate pre-treatment trends and explore lagged post-treatment effects. Consistent with Cohen and Einav (2003), our updated estimates show that primary seatbelt laws are associated with a 5 to 9 percent reduction in fatalities among motor vehicle occupants. Estimated effects of secondary seatbelt laws are smaller in magnitude and sensitive to model choice.

Suggested Citation

  • Anderson, D. Mark & Liang, Yang & Sabia, Joseph J., 2022. "Mandatory Seatbelt Laws and Traffic Fatalities: A Reassessment," IZA Discussion Papers 15843, IZA Network @ LISER.
    • Handle: RePEc:iza:izadps:dp15843
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    References listed on IDEAS

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    1. David J. Houston & Lilliard E. Richardson, 2007. "Risk Compensation or Risk Reduction? Seatbelts, State Laws, and Traffic Fatalities," Social Science Quarterly, Southwestern Social Science Association, vol. 88(4), pages 913-936, December.
    2. Garbacz, Christopher, 1991. "Impact of the New Zealand Seat Belt Law," Economic Inquiry, Western Economic Association International, vol. 29(2), pages 310-316, April.
    3. Goodman-Bacon, Andrew, 2021. "Difference-in-differences with variation in treatment timing," Journal of Econometrics, Elsevier, vol. 225(2), pages 254-277.
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    11. Lauren E. Jones & Nicolas R. Ziebarth, 2016. "Successful Scientific Replication and Extension of Levitt (2008): Child Seats are Still No Safer Than Seat Belts," Journal of Applied Econometrics, John Wiley & Sons, Ltd., vol. 31(5), pages 920-928, August.
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    JEL classification:

    • C13 - Mathematical and Quantitative Methods - - Econometric and Statistical Methods and Methodology: General - - - Estimation: General
    • I12 - Health, Education, and Welfare - - Health - - - Health Behavior
    • K32 - Law and Economics - - Other Substantive Areas of Law - - - Energy, Environmental, Health, and Safety Law
    • K42 - Law and Economics - - Legal Procedure, the Legal System, and Illegal Behavior - - - Illegal Behavior and the Enforcement of Law

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