And this problem is on the rise all over the country. Last year, police in New York City arrested around 50,000 people for marijuana possession. Pot has been decriminalized in New York since 1977, but displaying the drug in public is still a crime. So police officers stop people who look "suspicious," frisk them, ask them to empty their pockets, then arrest them if they pull out a joint or a small amount of marijuana. They're tricked into breaking the law. According to a report from Queens College sociologist Harry Levine, there were 33,775 such arrests from 1981 to 1995. Between 1996 and 2010 there were 536,322.