In Washington State, one of the first to legalize recreational marijuana, fatal crashes involving THC more than doubled within five years of the drug being legalized.
Triple-A Texas' Joshua Zuber says it's simple.
"If you're going to use marijuana, don't drive. If you plan to drive, don't use marijuana."
Zuber says Washington State's pot-related driving fatalities were under 9-percent in the five years before legalization.
"That share rose to 18% between 2013 and 2017, the five years after recreational use of marijuana was legalized."
For that reason, Triple-A opposes legalizing recreational marijuana.
Texas already leads the nation in driving deaths; Triple-A doesn't want to see that increase with recreational marijuana use.
"The new research supports the finding of an earlier study; it too found a sharp increase in the percentage of drivers involved in fatal crashes who were THC positive. So, because of its inherent traffic safety risk, Triple-A opposes legalizing marijuana for recreational use."
A Triple-A survey found about 15-million drivers admit getting behind the wheel within an hour after using marijuana in the past 30 days.