Medical cannabis and automobile accidents: Evidence from auto insurance

Health Econ. 2022 Sep;31(9):1878-1897. doi: 10.1002/hec.4553. Epub 2022 Jun 12.

Abstract

While many states have legalized medical cannabis, many unintended consequences remain under-studied. We focus on one potential detriment-the effect of cannabis legalization on automobile safety. We examine this relationship through auto insurance premiums. Employing a modern difference-in-differences framework and zip code-level premium data from 2014 to 2019, we find that premiums declined, on average, by $22 per year following medical cannabis legalization. The effect is more substantial in areas near a dispensary and in areas with a higher prevalence of drunk driving before legalization. We estimate that existing legalization has reduced health expenditures related to auto accidents by almost $820 million per year with the potential for a further $350 million reduction if legalized nationally.

Keywords: Cannabis; auto safety; automobile insurance; dispensary; insurance pricing.

MeSH terms

  • Accidents, Traffic
  • Automobiles
  • Cannabis*
  • Humans
  • Insurance*
  • Legislation, Drug
  • Medical Marijuana*

Substances

  • Medical Marijuana