Examination of the Legalization and Decriminalization of Marijuana on the DWI System: Measuring the Effect

The legalization of marijuana is receiving intense media attention throughout the country, and many States are considering whether they should legalize marijuana for recreational use. States need information on the impact of increased marijuana use on the safety of their citizens, including the safety of citizens who are not using the drug themselves.This project, which includes two stages, will examine how a State’s Driving While Intoxicated/Impaired (DWI) system evolves with the legalization of recreational marijuana. This project will “tell the story” of issues the arrest, prosecution, adjudication, and administrative systems face with a potential increase in drivers positive for marijuana. Lawmakers, State governments, the National Highway Traffic Safety Administration (NHTSA) and other federal agencies are the primary audience for the project results. The first stage, which is now complete, convened an expert panel. Stage two of the project will examine the legalization and/or decriminalization of recreational and/or medical marijuana in specific States using the measures the expert panel identified as feasible, relevant, and available to be collected.

  • Supplemental Notes:
    • This study is being conducted under the National Cooperative Research and Evaluation Program (NCREP), which is administered by the National Highway Traffic Safety Administration (NHTSA) and jointly managed by NHTSA and the Governors Highway Safety Association.


  • English


  • Status: Active
  • Funding: $304,959
  • Contract Numbers:


  • Sponsor Organizations:

    National Highway Traffic Safety Administration

    1200 New Jersey Avenue, SE
    Washington, D.C.  United States  20590

    Governors Highway Safety Association

    444 N. Capitol Street, NW, Suite 722
    Washington, DC  United States  20001

    Office of Behavioral Safety Research

    1200 New Jersey Avenue, SE
    Washington, District of Columbia  United States  20590
  • Project Managers:

    Smither, DeReece

  • Performing Organizations:

    Virginia Polytechnic Institute and State University, Blacksburg

    Virginia Tech Transportation Institute
    3500 Transportation Research Plaza
    Blacksburg, VA  United States  24061
  • Start Date: 20150801
  • Expected Completion Date: 20231231
  • Actual Completion Date: 0
  • USDOT Program: Behavioral Safety Research
  • Subprogram: Drug Impaired Driving

Subject/Index Terms

Filing Info

  • Accession Number: 01641222
  • Record Type: Research project
  • Source Agency: National Highway Traffic Safety Administration
  • Contract Numbers: DTNH22D00231-0003
  • Files: RIP, USDOT
  • Created Date: Jul 19 2017 10:49AM