Supreme Court Justice Louis Brandeis famously praised the division of sovereign powers included within America's constitutional structure for its capacity to encourage states to "serve as a laboratory; and try novel social and economic experiments without risk to the rest of the country." This legislative freedom is constrained, however, by various constitutional restrictions including the Supremacy Clause, which provides that federal law "shall be the supreme Law of the Land." Pursuant to this established principle of federal legal preeminence, any state law that conflicts with federal law is generally considered preempted and therefore void. Although simple in theory, the task of determining whether a state law is "in conflict" with federal law can be incredibly complex in practice. The ongoing national debate over marijuana provides a clear example of the confusion associated with the states' ability to pursue policies that deviate from those advanced by the federal government. In addition to the 20 states and the District of Columbia that currently exempt qualified users of medicinal marijuana from penalties imposed under state law, Colorado and Washington in late 2012 became the first states to legalize, regulate, and tax small amounts of marijuana for personal (i.e., nonmedicinal) use by individuals over the age of 21. These broad legalization initiatives stand in stark contrast to federal law, which makes the cultivation, distribution, or possession of any amount of marijuana—for any purpose other than bona fide, federally approved scientific research—a criminal offense. Therefore, the possession, cultivation, or distribution of marijuana remains a federal crime within Colorado, Washington, and every other state. As a result, individuals who grow, possess, use, sell, transport, or distribute marijuana, even when done in a manner consistent with state law or pursuant to a state-issued license, are nonetheless in violation of the federal Controlled Substances Act (CSA) and remain subject to federal criminal prosecution or other consequences under federal law. Given the federal government's continued ability to enforce its own prohibition, it cannot be said that the Washington and Colorado laws create a right to use marijuana. Nor does compliance with state law provide a defense to a prosecution brought under federal law. Nevertheless, President Obama expressed to Barbara Walters on ABC's Nightline program in a December 2012 television interview that in the hierarchy of federal drug enforcement priorities, his Administration has "bigger fish to fry" than arresting recreational marijuana users in jurisdictions where such use is authorized by state law. His personal views on this topic were later reflected in an August 2013 memorandum authored by the Deputy Attorney General, which instructed all federal prosecutors to use their "limited investigative and prosecutorial resources" toward certain specified marijuana-related criminal activities that the Obama Administration wants most to prevent, such as the distribution of marijuana to minors, the growing of marijuana on public lands, and the flow of revenue from marijuana sales to criminal enterprises, gangs, and cartels. The memorandum implied that the federal government's drug enforcement priorities would likely not include prosecuting individuals or organizations engaged in marijuana activities that are conducted in clear compliance with state laws that permit and regulate them. The memorandum noted, however, that "Congress has determined that marijuana is a dangerous drug" that remains illegal under federal law. The memorandum is an example of the doctrine of prosecutorial discretion, which gives the U.S. Department of Justice (DOJ) great leeway in choosing whether, and to what extent, to bring criminal prosecutions for violations of the Controlled Substances Act. However, a new Administration in the White House could easily change this federal approach toward marijuana. Approved by a majority of Washington voters in November 2012, Washington Initiative 502 legalizes marijuana possession by amending state law to provide that the possession of small amounts of marijuana "is not a violation of this section, this chapter, or any other provision of Washington law." Under the Initiative, individuals over the age of 21 may possess up to one ounce of dried marijuana, 16 ounces of marijuana infused product in solid form, or 72 ounces of marijuana infused product in liquid form. However, marijuana must be used in private, as it is unlawful to "open a package containing marijuana ... or consume marijuana ... in view of the general public." In addition to legalizing possession, the Initiative provides that the "possession, delivery, distribution, and sale" by a validly licensed producer, processor, or retailer, in accordance with the newly established regulatory scheme administered by the state Liquor Control Board (LCB), "shall not be a criminal or civil offense under Washington state law." The Initiative establishes a three-tiered production, processing, and retail licensing system that permits the state to retain regulatory control over the commercial life cycle of marijuana. Qualified individuals must obtain a producer's license to grow or cultivate marijuana, a processor's license to process, package, and label the drug, or a retail license to sell marijuana to the general public. The Initiative establishes various restrictions and requirements for obtaining the proper license and directs the state LCB to adopt procedures for the issuance of such licenses. On October 16, 2013, the LCB adopted detailed rules for implementing Initiative 502. These rules describe the marijuana license qualifications and application process, application fees, marijuana packaging and labeling restrictions, recordkeeping and security requirements for marijuana facilities, and reasonable time, place, and manner advertising restrictions. According to the adopted rules, Washington will impose an excise tax of 25% of the selling price on each marijuana sale within the established distribution system. The state excise tax will, therefore, be imposed on three separate transactions: the sale of marijuana from producer to processor, from processor to retailer, and from retailer to consumer. All collected taxes are deposited into the Dedicated Marijuana Fund and distributed, mostly to social and health services, as outlined in the Initiative. The Initiative also specifically provides that operation of a motor vehicle while under the influence of marijuana remains a crime. As of the date of this report, recreational marijuana retail stores have yet to open in Washington, although the LCB has received well over 3,000 applications to grow, process, or sell marijuana. The LCB has estimated that the application review process may take approximately 90 days to complete and that the state may begin issuing licenses by the end of February 2014. Unlike the relatively specific Initiative 502, Colorado Amendment 64 provides only a general framework for the legalization, regulation, and taxation of marijuana in Colorado—leaving regulatory implementation to the Colorado Department of Revenue. In November 2012, Colorado voters approved an amendment to the Colorado Constitution to ensure that it "shall not be an offense under Colorado law or the law of any locality within Colorado" for an individual 21 years of age or older to possess, use, display, purchase, consume, or transport one ounce of marijuana; or possess, grow, process, or transport up to six marijuana plants. Unlike Initiative 502, which permits only state-licensed facilities to grow marijuana, Amendment 64 allows any individual over the age of 21 to grow small amounts of marijuana (up to six plants) for personal use. Marijuana may not, however, be consumed "openly and publicly or in a manner that endangers others." In addition, the amendment also provides that it shall not be unlawful for a marijuana-related facility to purchase, manufacture, cultivate, process, transport, or sell larger quantities of marijuana so long as the facility obtains a current and valid state-issued license. However, the amendment expressly permits local governments within Colorado to regulate or prohibit the operation of such facilities. By comparison, Washington's Initiative 502 does not expressly allow Washington cities to ban marijuana stores from opening within their borders, and there is uncertainty about the degree to which such local prohibitions or moratoriums on the operation of recreational marijuana businesses may be enforced. Amendment 64 appears to envision a three-tier distribution and regulatory system, similar to that established in Washington, involving the licensing of marijuana cultivation facilities, marijuana product manufacturing facilities, and retail marijuana stores. In December 2012, Governor John Hickenlooper established the Amendment 64 Implementation Task Force (Task Force) to "identify the legal, policy and procedural issues that need to be resolved, and to offer suggestions and proposals ... that need to be taken" to effectively implement Amendment 64. The Task Force issued a final report on March 13, 2013, consisting of 58 recommendations. Of those recommendations, the most significant include establishing a "vertical integration" model in which "cultivation, processing and manufacturing, and retail sales must be a common enterprise under common ownership"; imposing the required 15% excise tax while preserving the option for a future marijuana sales tax; restricting commercial licenses to grow, process, or sell marijuana to state residents only; and permitting both residents and nonresidents to purchase marijuana, but imposing more restrictive limits on the quantity of marijuana that may be purchased by out-of-state consumers (a quarter ounce versus an ounce for individuals with a Colorado state-issued identification card). To implement Amendment 64, the Colorado General Assembly passed three bills that were signed into law by Governor Hickenlooper on May 28, 2013. On September 9, 2013, the Colorado Department of Revenue and State Licensing Authority adopted regulations to implement licensing qualifications and procedures for retail marijuana facilities. The regulations establish procedures for the issuance, renewal, suspension, and revocation of licenses; provide a schedule of licensing and renewal fees; and specify requirements for licensees to follow regarding physical security, video surveillance, labeling, health and safety precautions, and product advertising. On November 5, 2013, Colorado voters approved a 25% tax on retail marijuana (a 15% excise tax that would raise revenues to be used for public school capital construction, and an additional 10% sales tax that would generate revenues to fund the enforcement of the retail marijuana regulations). On December 23, 2013, the Colorado Marijuana Enforcement Division issued its first recreational marijuana licenses to 348 businesses (136 retail stores, 31 product companies, 178 growing facilities, and 3 testing laboratories). While these businesses have been granted state approval to produce and sell marijuana, they may also have to gain the licensing approval from local governments prior to their operation.