Phillip Boffey, writing in The New York Times acknowledges that marijuana is not harmless, “but, on balance, its downsides are not reasons to impose criminal penalties on its possession, particularly not in a society that permits nicotine use and celebrates drinking.”
“Marijuana’s negative health effects are arguments for the same strong regulation that has been effective in curbing abuse of legal substances … There is already some early evidence that regulation would also help combat teen marijuana use, which fell after Colorado began broadly regulating medical marijuana in 2010.”
“There’s no need to ban a substance that has less than a third of the addictive potential of cigarettes, but state governments can discourage heavy use through taxes and education campaigns and help provide treatment for those who wish to quit.”
Chart from Weedist