Adults over the age of 21 will be able to use cannabis for recreational purposes in California, Maine, Massachusetts, and Nevada.
Meanwhile, constituents in Arkansas, Florida, and North Dakota voted to decriminalize medical marijuana. And in Montana, residents voted to strike down a series of restrictions that limited medical use of marijuana.
Arizona, however, was the only state in which the measure looking to legalize marijuana for recreational purposes didn't pass.
Residents of Arkansas, Florida, and North Dakota will decide if the use of marijuana for medical purposes will be decriminalized. Meanwhile, Montana will decide whether to loosen the restrictions on the state's current medical marijuana law.
Update: October 6, 2016: Voters in at least five states will decide whether to legalize marijuana for recreational use this November. Ballot initiatives on the question are set to appear in front of voters in Arizona, California, Maine, Massachusetts, and Nevada this year, according to the Marijuana Policy Project. Ahead, a look at laws across the country as of earlier this year.
This year alone there have already been more than 50 legislative initiatives around the country aimed at legalizing or decriminalizing medical or recreational marijuana.
Alaska, Colorado, Oregon, Washington state, and Washington, D.C., have already legalized recreational, as well as medical, marijuana for adults (although in D.C., it still isn't legal to buy).
And 20 more states have legalized medical marijuana: Arizona, California, Connecticut, Delaware, Hawaii, Illinois, Maine, Maryland, Massachusetts, Michigan, Minnesota, Montana, Nevada, New Hampshire, New Jersey, New Mexico, New York, Pennsylvania, Rhode Island, and Vermont. The state moves haven't changed federal marijuana policy, though — the Office of National Drug Control Policy notes that "these state marijuana laws do not change the fact that using marijuana continues to be an offense under federal law."
This year could see marijuana legalized for recreational use in an additional 10 states, including Connecticut, Hawaii, and Michigan. Seven other states considered that legislation this year, but the bills either died or missed their deadlines. Marijuana could also be legalized for medical use in Louisiana, Missouri, North Carolina, South Carolina, South Dakota, and Tennessee.
The Marijuana Policy Project (MPP) is backing six of those state ballot initiatives. And the group hopes the political climate will be favorable for getting voters to say yes.
"Presidential election years are the most important years for marijuana policy reform ballot issues, since younger, more supportive voters show up in greater numbers for those elections," Morgan Fox, communications manager at the MPP, told Refinery29.
This year, 15 states have also considered laws that would decriminalize marijuana, e.g. prohibit jailing people for possessing small amounts of the drug — though six of those bills have died or missed their legislative deadlines, according to the MPP.
Fox noted that decriminalizing and legalizing marijuana do not necessarily go hand in hand. "Some states that have decriminalized marijuana are not even close to passing laws to regulate marijuana," he told Refinery29.
Marijuana reform proponents argue that legalizing and decriminalizing the drug is both ethically and fiscally advantageous.
Last year, President Obama suggested that decriminalizing marijuana possession would save the United States money in incarceration costs. The move toward decriminalization, whether or not it's connected to legalization, could help the U.S. economy.
"You're starting to see not just liberal Democrats, but also some very conservative Republicans recognize [prohibition] doesn't make sense, including sort of the libertarian wing of the Republican Party," President Obama told Vice News last March. "They see the money and how costly it is to incarcerate. So, we may actually be able to make some progress on the decriminalization side."
The 2016 election could also impact federal marijuana laws, as Hillary Clinton has proposed classifying marijuana as a Schedule II drug. It is currently a Schedule I drug, which is defined as having "no currently accepted medical use," according to the Drug Enforcement Administration.