According to the website Autoblog.com fatal crashes involving marijuana rise just prior to and during April 20th, then drop back to 'regular' levels.

For those of you who don't sear your lungs, High Times Magazine is said to be responsible for declaring April 20th as 4-20 day, or the official day to 'get high', this was done about 25 years ago. The origin dates back as far as 1971 when some say it was a time of day to enjoy a 'smoke,' 4:20pm.

Then, in 1991 the story began that 420 was police code in San Rafael, CA for "marijuana smoking in progress."

At any rate, it is now observed nationwide by pot smokers as their 'holiday.' But it's also apparently the day when fatal crashes involving impaired drivers rise by 12 percent.

The University of British Columbia has analyzed National Traffic Safety Administration (NTSA) data from 1992 through 2016. Traffic fatalities just prior to and during 4-20 were 12 percent higher than normal. For drivers under the age of 21, the increase was 38%.

The study said the risks and statistics were comparable to those found for drivers on Super Bowl Sunday, especially after the conclusion of the game. It's been found that after the Big Game is over, there's a definite spike in impaired driving and fatalities.