According to 2015 findings from the Pew Research Center, nearly half (49%) of Americans say that they have tried marijuana for either medicinal or recreational use. Although the drug is legal or decriminalized in some U.S. states, it is still illegal under federal law—listed as a Schedule I substance under the Controlled Substances Act of 1970.

However, there seems to be a trend of relaxation when it comes to prohibitive legislation. Let's take a look at the past, present and future of marijuana law in the USA.