Police dispatch code for smoking pot is 420. The number 420 is not police radio code for anything, anywhere. Checks of criminal codes suggest that the origin is neither Californian nor federal. For instance, California Penal Code 420 defines as a misdemeanor the hindrance of use of public lands.
There are approximately 420 active chemicals in marijuana. Actually, there are approximately 315 active chemicals in marijuana. This number goes up and down depending on which plant is used.
April 20th is National Pot Smokers Day. Well, it is now; but that wasn’t the origin.
April 20th is Hitler’s birthday. Yes, it is his birthday. But, as 420 started out as a time, not a date, his birthday had nothing to do with it.
THE REAL ORGIN
Back in 1971, some kids at San Rafael High School in California used to meet outside the school to smoke weed every day at 4:20 P.M. So their code to meet was “4-20.” They eventually started using “4-20″ to describe EVERYTHING related to marijuana . . . and the term spread when they used it around traveling GRATEFUL DEAD fans, who adopted it. Eventually, “High Times” magazine heard about the “4-20″ term through the Dead fans, and took it to an even wider audience. And since April 20th is 4/20, it became the unofficial holiday for weed smokers. And there you have it!