In this April 2, 2016 file photo, a demonstrator waves a flag with marijuana leaves on it during a protest calling for the legalization of marijuana, outside of the White House in Washington.

Risk of stoned driver crashes grows as legal marijuana spreads across U.S., according to study

As the push to legalize marijuana gains momentum, so is evidence that more permissive policies on the drug are putting motorists at risk.

The Insurance Institute for Highway Safety found, in a study to be released on Thursday, that traffic accidents are rising in states that have legalized recreational marijuana. That followed stark warnings from the National Transportation Safety Board, which on Tuesday issued several recommendations to combat drug-impaired driving.

“The last thing in the world that we want is to introduce another legal substance where we may be adding to that toll and to the carnage on our highways,” said David Harkey, president of the Insurance Institute. “With marijuana impairment, we’re just now starting to understand what we don’t know.”

Read the rest of this story on DenverPost.com.