US traffic fatalities and relationship to medical cannabis laws

Guest blogger Kayla Matthews reports on recent research that finds states that have enacted laws legalizing medical marijuana see a reduction in vehicle-related fatalities.


There’s been a great deal of discussion about the ethical and practical implications of medical cannabis laws, with an increasing number of states enacting legislation allowing people to use marijuana to treat symptoms of various ailments. It remains a controversial practice, however, and both sides are always interested in new research both for and against the practice.

Medical marijuana is currently legal in 28 U.S. states and the District of Columbia. The recommendation process in most of these states is fairly straight-forward, but what kinds of related effects are these areas seeing from medical cannabis adoption?

A study published recently in the American Journal of Public Health indicates states that have enacted laws legalizing medical marijuana see a reduction in vehicle-related fatalities, both immediately and over time.

Fatalities decrease in states with medical marijuana laws

The study examined data in the Fatality Analysis Reporting System over nearly three decades to determine the relationship between fatal traffic accidents and medical marijuana laws (MML). States with MML showed lower rates of traffic fatalities than states without them.

There were some distinctions between age groups. States with MML showed immediately lower traffic fatality rates for people in the 15- to 24-year-old group and the 25- to 44-year-old group. There were also a smaller number of fatalities in states with MMLs in subsequent years for the latter age group.

Variations among states also occurred. When the data was analyzed by state, just seven states showed reductions in traffic fatalities after the enactment of MML. The authors noted that specific local factors could be in play.

The study could have a great impact on future MMLs, including implementation, repealing of the laws or a wider adoption of them.

Medical marijuana legalization also decreases opioid use

It is one of several studies over the past several months to indicate positive effects of the legalization of medical marijuana on opioid use and vehicle deaths. Another American Journal of Public Health study examined Fatality Analysis Reporting System data from 68,394 individuals who were fatalities in a car crash over the period 1999 to 2013. The data came from 18 states.

The data cited by U.S. News and World Report indicated MML was associated with less chance of individuals testing positive for opioids after their car-crash-related deaths. The reduction was specially seen in drivers between the ages of 21 and 40.

Researchers note that the effects in the roughly 20- to 44-year-old age group was likely due to the age groups involved in medical marijuana use. Many states restrict medical marijuana use to people 21 years old or older. Most medical marijuana users are under the age of 45.

Fewer opioid prescriptions

Medical marijuana is prescribed for a number of conditions, including pain. In the past, opioids have been one of the prevailing methods used to treat chronic and severe pain. However, opioid use can lead to addiction, abuse and overdoses. There were more than 28,000 overdose deaths in 2014, according to U.S. News, including heroin overdoses.

Researchers in this second study note that data indicate that medical marijuana is being prescribed for pain and thus lessening prescriptions of opioids for pain.

Both studies indicate opioid use decreases when marijuana is legalized for medical use. This is potentially good news, as it may lessen the epidemic use of opioids. Since marijuana has increasingly been legalized for recreational use in multiple states, this type of use vis-à-vis opioids and other painkillers is a potential area of further study.

More fuel for the debate

These studies are merely the latest in the growing canon of research on medical marijuana laws and how they impact people. Doubtless there will be more studies in the future that provide a more substantive reason behind the link between car fatalities and medical cannabis, but only time will tell what those revelations are.

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