Marijuana makes you HIGH, correct? What happens when the Cannabis wears off? Well, you get LOW. And since you are feeling really low, then Little Things can set you off and you become very angry, e.g. A Fender Bender turns into Road Rage.
That is, a Marijuana "Coming Down" = Very Irritable.
Due to the many Social Carrots feeding their Marijuana addictions, the Homeless have become very aggressive in panhandling for drug money via
(a) knocking on car windows at traffic lights,
(b) to following shoppers at malls asking for money or
(c) even stopping cars in heavy street traffic.
Some Researchers say Lead Poisoning could be to blame for Black Kids being 4 times more likely to be disciplined than Whites Kids and ADHD. However, Second-Hand Marijuana Smoke from the parents (or the mother's boyfriends) could cause Very High Irritability in these school kids.
Note: A Contact High is not the same as a Bad Takeoff.