Earlier this week, Washington Initiative 502 (I-502), a marijuana law reform measure which appeared on the November 2012 general ballot, won the popular vote passing by a margin of approximately 55% to 45%. As a result, beginning on December 6, 2012, the initiative that is now law will make it legal for persons aged twenty-one years and over to possess a limited amount of marijuana for recreational use.

Washington State was joined by Colorado in making history this week. On Tuesday night, Colorado voters passed Amendment 64, a measure seeking the legalization of marijuana for recreational use by adults, by 55% to 45%, a margin identical to Washington State’s. A similar measure in Oregon was not as successful. Measure 80, Oregon’s own measure to legalize possession and recreational use of marijuana, was rejected by voters.

The controversial new Washington law does more than simply legalize marijuana possession. It will also remove state-law prohibitions against producing, processing, and selling marijuana, it will subject producers, processors, and retailers to a licensing requirement and other regulation by the Washington State Liquor Control Board, and it will impose a 25% excise taxes on wholesale and retail sales of marijuana, earmarking revenue for purposes that include substance-abuse prevention, research, education, and healthcare. Additionally, laws prohibiting driving under the influence will be amended to include maximum thresholds for THC blood concentration.

Over the course of the next year, the Washington State Liquor Control Board will be charged with carrying out the will of Washington State voters. By December 31, 2013, the Board must develop a new framework of regulations to fully implement the new system.

I-502 was originally submitted to the Washington Secretary of State on May 10, 2011 by John McKay, the former United States Attorney for the Western District of Washington. By the end of December 2011, proponents had collected enough signatures to meet the 241,153 registered voter signature requirement. The measure was subsequently sent to the legislature. However, in April 2012, the Washington State legislature adjourned without action, and I-502 automatically advanced to the November 2012 general ballot.

Now that marijuana legalization measures have been approved in both Washington and Colorado, scholars, legislators, and policy makers are trying to determine how the law will work in practice due to the laws’ direct conflict with federal law. Marijuana is classified as a Schedule 1 controlled substance under the Federal Controlled Substances Act, making it subject to federal enforcement action. This week, Department of Justice officials reminded voters that federal law “remains unchanged.” The agency plans to review the Washington and Colorado legalization measures in the coming weeks.