The historical roots of cannabis vary widely and run parallel to the development of the Silk Road. Accordingly, the plant was first used by the Chinese empires, followed by the Persian empire, and then introduced to western Europe around the 16th century, appearing as an herbal medicine in botany texts.
Following the trade routes, the cultivation of hemp in North America was not only legal, but mandatory under King James I. Likewise, several American founders, including George Washington, referenced growing hemp alongside tobacco in the 18th century.
The use of cannabis for THC purposes in US was first reported widely in the 19th century. THC was introduced to European soldiers en masse during the age of imperialism and subsequently imported to Europe. It became popular amongst the European bourgeoisie and spread quickly to their counterparts in the US. Likewise, smoking marijuana was popular amongst Mexican immigrants in the 19th Century, who introduced the practice to their southwestern neighbors without sanction.
By the turn of the 20th century, cannabis could be found in most pharmacies as an over-the-counter remedy for a variety of physical ailments. However, moralists blamed adulterated substances for uncharacteristically violent behavior, and the newly minted Food and Drug Administration labeled marijuana a poison.
In the 1920s, cannabis was a target of the Prohibition movement. By the 1930s, a majority of states adopted bans against marijuana. The Uniform Narcotics Act was proposed to states from the Federal Bureau of Narcotics. Notably, the 1936 film "Tell Your Children," was widely distributed with the intent of warning children of the dangers of cannabis. Subsequently, the Marihuana Tax Act of 1937 placed a relatively small federal tax on the sale of small amounts of marijuana, but it did not criminalize it on the federal level. Subsequently, "Tell Your Children" became popular much later as an unintentional comedy known as "Reefer Madness," which is still available today.
State regulations varied with the turn of the 20th century. The Boggs Act of 1952 and the Narcotics Control Act of 1956 established and increased federal mandatory minimum sentencing for possession of the substance.The Controlled Substances Act of 1970 labeled cannabis a Schedule I drug as part of the War on Drugs, revoking the previous minimum sentences and re-enforcing beliefs that marijuana was a dangerous substance.
Recent court decisions have generally upheld the use of marijuana as a crime. However, the Alaska Supreme Court ruled in 1975 that private use of a small amount of marijuana in one's home was protected under a constitutional right to privacy, effectively lifting the state ban on some uses of the substance. Alternatively, the Supreme Court of the United States addressed the issue in two recent cases from California, where it established that private distribution of medical marijuana continues to be a federal crime, regardless of the state's referendum to allow it.
The US War on Drugs started in earnest during the 1970's. The US Congress passed the Comprehensive Drug Abuse Prevention and Control Act in 1970, following the spread of recreational drug use during the 1960's and of drug addictions of US soldiers serving in the Vietnam War. Particularly troubled by the addictions of US soldiers, in 1971 US President Richard Nixon declared, "America's public enemy number one in the US is drug abuse" and announced his plan for an offensive against drugs. He requested that Congress increase the US budget to enforce anti-drug laws and treat drug addiction from $195 million to $350 million. By 2013, the US government spent over one trillion dollars fighting a war on drugs.
In the decades since Nixon launched the War on Drugs, the US has fought against drugs both abroad and at home. The Drug Enforcement Administration, created [PDF] by Nixon in 1973, established bases in foreign countries to combat the drug trade. The most prominent foreign theater of operations has been Latin America, where the US has maintained a harsh anti-drug policy that discouraged legalization or reduced penalties. By 2013, Latin American leaders voiced their opposition to the anti-drug policies of the US and blamed the high demand for drugs within the US as a contributing factor to failed initiatives. Though reports about the spillover of Mexico's drug-related violence into the US remain contested, the increased activity of US border patrols for security purposes calls into question the overall success of the war in Latin America.
The most critiqued theater of the War on Drugs, however, has been the home front. According to the American Civil Liberties Union, domestic drug enforcement operations disproportionately affect persons of color. In comparison to the white population, African-American males are nearly four times more likely to be arrested for marijuana possession. Certain laws also target drugs that are predominantly used by minority populations, such as crack cocaine. The debate continues in the US. In September 2013, Senator Rand Paul compared the War on Drugs to Jim Crow laws because of its disparate impact on racial minorities.
Marijuana is illegal in the US under a variety of federal statutes that criminalize the production, distribution and possession of the substance for any purpose. Regardless, laws in 23 states, the District of Columbia and Guam permit for some legal use of the substance. This ranges from the legalization of full recreational use in Colorado, Washington, Oregon, Alaska and Washington D.C. to the narrower allowance for medicinal use as a defense in court in Maryland. Most of the 23 states only permit the use of small quantities of the substance for medical purposes. The diversity of approaches to the level at which marijuana is legal, coupled with the conflicts with federal law, makes for a complicated history and present state of laws.
The avenues through which states have moved towards legalization of marijuana have been mostly popular vote referenda or the passage of standard legislative acts. In 1998, the District of Columbia city council became the first elected body to pass a bill legalizing medical marijuana. This then went on to pass by popular vote. Due to the federal control of the District by Congress, this attempt was halted, delaying the legalization of medical marijuana there until 2010. California was the first state to legalize medical marijuana through popular vote in 1996 through an amendment to the state constitution. Alaska was the first state to legalize it through legislative activity in 1999, following several failed attempts earlier.
Washington and Colorado were the first two states to legalize marijuana for recreational use. In Colorado [PDF], this was achieved through an amendment to the state constitution that passed with a 55 percent popular vote. The Washington bill [PDF] was an initiative put before the legislature in 2011 that went to popular vote due to legislative inaction and passed by 55.7 percent of the popular vote. A similar initiative was attempted in Oregon [PDF] but failed to pass the popular vote.
Following the passage of these bills, the state administrative agencies have worked to establish rules and protocol on how the substance's legalization will work. This has been especially complicated due to the conflict with federal law. The Department of Justice announced in August 2013, however, that they had amended their marijuana enforcement policies and would not interfere with states experimenting with legalization.
Several states have recently decriminalized the possession of marijuana, including Vermont and Maryland. Still more states are moving towards legalizing medical marijuana for the first time, including Illinois, where a bill was passed and signed into law in August 2013 to start their medical marijuana program on January 1, 2014. On October 28, 2013, the ACLU filed a lawsuit challenging the Arizona medical marijuana law. Through that suit, the ACLU was able to establish that marijuana extracts do fall under the allowed use of marijuana for medical purposes under the Arizona law.