BOSTON (CBS) – The state is asking drivers to be on high alert on Friday, as research shows the April 20 date brings an increase in the number of drivers under the influence of marijuana.
A recent study by the Journal of the American Medical Association found a 12 percent increase in deadly crashes on April 20 after 4:20 p.m.
The number 420 has become associated with marijuana use. The reason why traces back to a California high school in the 1970s.
As the story goes, students would meet at 4:20 p.m. each day on campus to smoke marijuana. The group developed a relationship with the Grateful Dead, and the band helped the term become more widespread.