Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2014 Jul 1:140:137-44.
doi: 10.1016/j.drugalcdep.2014.04.008. Epub 2014 Apr 23.

Trends in fatal motor vehicle crashes before and after marijuana commercialization in Colorado

Stacy Salomonsen-Sautel  1 , Sung-Joon Min  2 , Joseph T Sakai  2 , Christian Thurstone  3 , Christian Hopfer  2
Affiliations

Trends in fatal motor vehicle crashes before and after marijuana commercialization in Colorado

Stacy Salomonsen-Sautel et al. Drug Alcohol Depend. .

Erratum in

  • Drug Alcohol Depend. 2014 Sep 1;142:360

Abstract

Background: Legal medical marijuana has been commercially available on a widespread basis in Colorado since mid-2009; however, there is a dearth of information about the impact of marijuana commercialization on impaired driving. This study examined if the proportions of drivers in a fatal motor vehicle crash who were marijuana-positive and alcohol-impaired, respectively, have changed in Colorado before and after mid-2009 and then compared changes in Colorado with 34 non-medical marijuana states (NMMS).

Methods: Thirty-six 6-month intervals (1994-2011) from the Fatality Analysis Reporting System were used to examine temporal changes in the proportions of drivers in a fatal motor vehicle crash who were alcohol-impaired (≥0.08 g/dl) and marijuana-positive, respectively. The pre-commercial marijuana time period in Colorado was defined as 1994-June 2009 while July 2009-2011 represented the post-commercialization period.

Results: In Colorado, since mid-2009 when medical marijuana became commercially available and prevalent, the trend became positive in the proportion of drivers in a fatal motor vehicle crash who were marijuana-positive (change in trend, 2.16 (0.45), p<0.0001); in contrast, no significant changes were seen in NMMS. For both Colorado and NMMS, no significant changes were seen in the proportion of drivers in a fatal motor vehicle crash who were alcohol-impaired.

Conclusions: Prevention efforts and policy changes in Colorado are needed to address this concerning trend in marijuana-positive drivers. In addition, education on the risks of marijuana-positive driving needs to be implemented.

Keywords: Alcohol-impaired driving; Drugged driving; Marijuana-positive driving; Medical marijuana; Traffic fatalities.

PubMed Disclaimer

Conflict of interest statement

Conflicts of Interest: Dr. Sakai received reimbursement in 2012 for completing a policy review for the WellPoint Office of Medical Policy & Technology Assessment (OMPTA), WellPoint, Inc., Thousand Oaks, CA. He also serves as a board member of the ARTS Foundation. All other authors report no biomedical financial interests or potential conflicts of interest.

Figures

Figure 1
Figure 1
Number of medical marijuana registered users from 2009–2011
Figure 2
Figure 2
Proportion of drivers in a fatal motor vehicle crash who were marijuana-positive in Colorado and 34 states without medical marijuana laws from 1994–2011
Figure 3
Figure 3
Proportion of drivers in a fatal motor vehicle crash who were alcohol-impaired in Colorado and 34 states without medical marijuana laws from 1994–2011
Figure 4
Figure 4
Number of motor vehicle-related fatalities in Colorado from 1994–2011
Figure 5
Figure 5
Number of motor vehicle-related fatalities in 34 states without medical marijuana laws from 1994–2011
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Anderson BM, Rizzo M, Block RI, Pearlson GD, O’Leary DS. Sex differences in the effects of marijuana on simulated driving performance. J Psychoactive Drugs. 2010;42:19–30. - PMC - PubMed
    1. Anderson MD, Hansen B, Rees DI. Medical marijuana laws, traffic fatalities, and alcohol consumption. J Law Econ. 2013;56:333–363.
    1. Bosker WM, Kuypers KP, Theunissen EL, Surinx A, Blankespoor RJ, Skopp G, Jeffery WK, Walls HC, van Leeuwen CJ, Ramaekers JG. Medicinal Delta(9)-tetrahydrocannabinol (dronabinol) impairs on-the-road driving performance of occasional and heavy cannabis users but is not detected in Standard Field Sobriety Tests. Addiction. 2012;107:1837–1844. - PubMed
    1. Bramness JG, Khiabani HZ, Morland J. Impairment due to cannabis and ethanol: clinical signs and additive effects. Addiction. 2010;105:1080–1087. - PubMed
    1. Downey LA, King R, Papafotiou K, Swann P, Ogden E, Boorman M, Stough C. The effects of cannabis and alcohol on simulated driving: influences of dose and experience. Accid Anal Prev. 2013;50:879–886. - PubMed

Publication types

Substances

LinkOut - more resources