A new study published by researchers from University of Texas at Austin looks at crash fatality rates after legalization of marijuana in both Washington and Colorado. The group of researchers looked at the annual motor vehicle crash data between 2009 and 2015 in both legalized states and used data from eight control states for correlation.
Year-over-year changes were the subject of the study, with the approach to find if marijuana legalization had an impact on crash fatality rates for every billion miles driven.
Data before and after legalization was considered and found that rates of fatal accidents didn’t vary drastically in Washington or Colorado when compared to the control states. Light truck and passenger occupants accounted for 65% of the 21,132 traffic fatalities in 2013.
The data suggests that marijuana legalization didn’t have a negative impact on the number of fatalities suffered during the six-year span. Statistically, there was no major difference found between both data sets.
The findings are a win for medical marijuana advocates, who state medical marijuana doesn’t have a major impact on automobile accidents.
The findings looked specifically at the number of fatal accident increases and conflicts, with a study conducted by the Insurance Institute for Highway Safety. The conflicting study found that recreation marijuana did have an impact on the rising number of crashes.
IIHS’s study also looked at Colorado and Washington, and used surrounding states for control data. The study found that the first states to legalize recreational use of marijuana experienced more crashes, but the size and impact of the crashes varies by state.
Insurance claims increased the most in Colorado, with claim rates rising 14% since legalization when compared to neighboring states: Utah, Nebraska and Wyoming. Washington’s figures were somewhat better, with rates of just 6.2% compared to neighboring states.
When combined, the first three states to legalize marijuana, including Oregon, had just a 3% difference in claims when compared to surrounding states.
Combined analysis uses a larger pool of states and accidents to provide a better overall representation on marijuana and its link to accident increases. The disparity of the study suggests that the increases is more drastic on a state-by-state comparison. Colorado has a 21% higher claim rate increase when compared to Utah, while it had just a 3% higher increase in claims when compared to Wyoming.
A large-scale study is ongoing to try and determine how legalization in Oregon impacts the risk of auto accidents and crashes. The results are expected to be released in 2020. The studies both look at the impact of marijuana in the three original states to legalize the drug.
The data does not include the five other states that have all legalized marijuana, as the comparison data doesn’t provide enough data points to make a clear correlation between usage and an increase in accidents.
Another 17 states have also allowed limited access to marijuana for medicinal usage and still consider recreational usage to be illegal. Drivers routinely state that alcohol is a bigger risk on the road than marijuana usage.