Marijuana Laws: Understanding Legalization And The Timeline

Marijuana laws are rapidly changing across the United States, with 24 states, Washington D.C., and Guam having acted to legalize recreational marijuana, and many others decriminalizing its use. The history of cannabis policy in the U.S. is long and varied, with the drug being legal and used medicinally between 1840 and 1900. In 1914, the Harrison Act was enacted, which declared drug use a crime, and in 1937, the Marijuana Tax Act imposed a tax on cannabis, effectively prohibiting its use. In 1970, the Controlled Substances Act categorized marijuana as a Schedule I substance, deeming it to have no acceptable medical use. However, in recent years, there has been a growing movement to relax marijuana laws, with states legalizing and decriminalizing its use, and public support for legalization rising rapidly.

Marijuana legalization at the state level

Marijuana laws are rapidly changing across the United States, with laws varying from state to state. Marijuana remains illegal at the federal level, but as of November 2024, 24 states, Washington D.C., and Guam have acted to legalize recreational marijuana.

The movement towards marijuana legalization gained momentum in 2012 when voters in Colorado and Washington approved ballot measures to legalize the recreational use and sale of cannabis, making them the first states to do so. Since then, public support for legalization has risen rapidly, with a growing majority of Americans believing that recreational marijuana should be legal. This includes a majority of both Democratic and Republican voters.

The legalization of marijuana at the state level has occurred in several stages, beginning with decriminalization, followed by legalization for medical use, and finally, in some states, legalization for recreational use.

Decriminalization

The process of decriminalization involves reducing the penalties for marijuana-related offenses, often removing the possibility of jail time for first-time offenses. As of April 2024, 31 states and Washington D.C. have decriminalized low-level marijuana possession offenses.

Medical Use

In 1996, California became the first state to legalize medical marijuana, and since then, over 40 states and Washington D.C. have followed suit.

Recreational Use

As of November 2024, 24 states, Washington D.C., and Guam have legalized recreational marijuana. The laws vary from state to state, with different provisions for the amount of marijuana an adult can possess, whether adults can grow their own plants, and how tax revenue from sales is spent.

The legalization of marijuana at the state level has been a complex and evolving process, with states grappling with how to regulate and tax the drug, while also addressing social justice concerns arising from the disproportionate impact of marijuana laws on minority communities.

Marijuana legalization at the federal level

The first regulation of marijuana at the federal level occurred with the 1906 Pure Food and Drug Act, which required that over-the-counter drugs containing cannabis be labeled. However, it was the 1937 Marihuana Tax Act that effectively prohibited cannabis by imposing heavy taxes and regulations, with failure to comply resulting in fines, jail time, or both. This act was deemed unconstitutional in 1969, and in 1970, the Controlled Substances Act established federal drug policy, classifying marijuana as a Schedule I drug with no accepted medical use and a high potential for abuse, making it illegal under federal law.

In recent years, there have been significant efforts towards marijuana reform at the federal level. The most substantial cannabis legislation introduced in 2023 was the Marijuana Opportunity Reinvestment and Expungement (MORE) Act, which aims for full federal legalization and includes a focus on equity provisions such as expungement for certain cannabis offenses. Other bills, like the States Reform Act of 2023 and the Strengthening the Tenth Amendment Through Entrusting States (STATES) 2.0 Act, would remove cannabis from the Controlled Substances Act entirely and task the Food and Drug Administration (FDA) with regulating cannabis products. These acts adopt different regulatory models, with the former resembling alcohol regulation and the latter allowing non-legal states to maintain prohibition while legalizing interstate commerce in state-compliant cannabis.

Additionally, the Marijuana 1-to-3 Act of 2023 takes a rescheduling approach by directing the Attorney General to transfer cannabis from Schedule I to Schedule III of the Controlled Substances Act. The Deferring Executive Authority (DEA) Act seeks to limit the Drug Enforcement Administration's (DEA) ability to reschedule cannabis without Congressional approval, while the Harnessing Opportunities by Pursuing Expungement (HOPE) Act of 2023 and the Clean Slate Act of 2023 aim to facilitate expungement and sealing of criminal records for non-violent cannabis offenses.

The PREPARE Act of 2023 directs the Attorney General to establish a commission to study a prompt approach to federal cannabis regulation, considering issues like the impact on low-income and minority communities, the industry's lack of access to financial services, and inconsistent product safety and labeling requirements. Other notable bills include the Free to Grow Act of 2023, which would repeal a restriction preventing individuals with felony convictions related to controlled substances from engaging in hemp production, and the Higher Education Marijuana Research Act of 2023, which would allow higher education institutions in legal jurisdictions to obtain cannabis for research purposes.

While marijuana legalization at the federal level has not yet been achieved, the variety of bills introduced in Congress reflects the dynamic nature of cannabis reform efforts and the ongoing pursuit of consistent regulation across the country.

The history of marijuana laws in the US

Marijuana laws in the US have a long and complex history, with the country's relationship to the substance evolving over the years. Here is a brief overview of the key moments in the history of marijuana laws in the US:

Early History

Before the 20th century, cannabis was legal in the United States and used for medicinal purposes. However, in 1860, concerns about the potential negative effects of cannabis use led to the creation of the first Federal commission to study the drug. By the 1890s, many medical professionals considered it a narcotic that should be regulated. Recreational cannabis use began at the start of the 20th century, and with it came a movement to regulate its use.

20th Century

In 1914, the Harrison Act was enacted, making drug use a crime. A year later, in 1915, California became the first state to criminalise cannabis possession. The drug was associated with Mexican immigrants, who had been flooding into the US following the Mexican Revolution of 1910, and the fear and prejudice surrounding these newcomers became attached to marijuana. This led to a flurry of research that linked marijuana use with violence, crime, and other deviant behaviours, mainly committed by "racially inferior" or underclass communities.

In the 1930s, the US Federal Bureau of Narcotics warned of the increasing abuse of cannabis, and the Marijuana Tax Act of 1937 effectively criminalised marijuana possession, restricting it to individuals who paid an excise tax for certain authorised medical and industrial uses. By 1942, marijuana had been removed from the US pharmacopeia.

Public sentiment towards marijuana began to shift in the 1960s and 70s, with a growing movement advocating for the reform of federal marijuana laws. During this time, eleven states took measures to decriminalise marijuana possession, and in 1978, New Mexico became the first state to recognise its legitimate medical use.

In 1996, California passed Proposition 215, becoming the first state to legalise the use of medical marijuana. This marked a turning point in marijuana laws across the US, with many other states following suit in the years since.

21st Century

Despite these changes at the state level, marijuana remains illegal at the federal level. However, federal law is generally not enforced in states where marijuana has been legalised for medical or recreational use. As of 2025, 39 states have legalised medical marijuana, and 24 states have legalised recreational use.

The legal status of marijuana in the US continues to evolve, with ongoing debates and ballot measures seeking to further relax or restrict marijuana laws across the country.

The pros and cons of marijuana legalization

Marijuana legalization refers to the practice of allowing and regulating the production, distribution, sale, and possession of cannabis so that its use within established rules is no longer a crime. Here are some of the pros and cons of marijuana legalization:

Pros

• Regulation of a safe drug: Legalization allows the government to enforce laboratory testing and regulations to ensure that marijuana is free of toxins. Regulations can also be implemented to prevent children's exposure to marijuana, such as child-resistant packaging and age restrictions on buyers.
• Ending costly and racist enforcement of marijuana laws: Legalization would end the costly enforcement of marijuana laws, which cost the United States between $1.19 billion and $6.03 billion annually. It would also address the racial disparity in the enforcement of these laws, where Black people are more likely to be arrested for marijuana possession despite similar usage rates between Black and White people.
• Debilitating the illegal marijuana market: Legalization would subvert the illegal marijuana market and reduce the demand for marijuana smuggled from Mexico, costing Mexican drug cartels billions in profits.
• Boosting the economy: The marijuana industry generates significant economic activity, with every $1 spent resulting in $2.13-$2.40 generated for other industries. Legalization also creates new tax revenue and jobs, with the industry creating over 400,000 American jobs as of 2022.
• Public support: A growing number of Americans support the legalization of marijuana, with polls showing that 59%-88% of Americans are in favour.

Cons

• Serious societal costs: Marijuana use can lead to increased emergency room visits, medical care, and addiction treatment. It can also impair driving skills, increasing the risk of car collisions.
• Negative environmental impact: Marijuana cultivation requires a significant amount of water and energy, contributing to water pollution, soil erosion, and greenhouse gas emissions.
• Creation of a "Big Marijuana" industry: Legalization could lead to the creation of a "Big Marijuana" industry that uses similar tactics to "Big Tobacco", appealing to children through colourful and branded products.
• Health risks: Health experts point to the health risks associated with marijuana use, including memory and cognition issues, lung damage, and an increased risk of accidents.

The process of marijuana legalization in individual states

Marijuana laws are rapidly changing across all 50 states in the US. As of January 2025, marijuana is legal in 39 states for medical use and 24 states for recreational use.

The process of marijuana legalization varies depending on the state, but typically follows a similar trajectory, beginning with decriminalization, followed by medical legalization, and finally, recreational legalization.

Decriminalization

Decriminalization is the first step towards legalization and involves reducing the penalties for marijuana possession and use. This can include lowering the charges for possession from a felony to a misdemeanor, or eliminating criminal penalties altogether, instead imposing civil fines or other punishments.

The first state to decriminalize marijuana was Oregon in 1973, which reduced the penalty for possession of up to one ounce to a $100 fine. Between 1973 and 1979, 11 states decriminalized cannabis possession. This trend continued in the 2000s, with several additional states passing decriminalization laws.

Medical Legalization

The next step towards legalization is allowing the use of marijuana for medical purposes. This typically involves passing legislation or ballot measures that permit the use of marijuana to treat certain medical conditions.

In 1996, California became the first state to legalize medical marijuana, and by 2025, 39 states had followed suit. To access medical marijuana, patients typically need a recommendation or prescription from a medical professional.

Recreational Legalization

The final step in the legalization process is permitting the use of marijuana for recreational purposes by adults. This usually involves ballot measures or acts of state legislature that legalize the possession, cultivation, and distribution of marijuana for personal use.

In 2012, Washington and Colorado became the first states to legalize recreational marijuana. By January 2025, 24 states and Washington, D.C., had legalized recreational use for adults aged 21 and older.

It's important to note that the process of legalization is not always linear, and some states may skip steps or move at a different pace. Additionally, even in states where marijuana is legal, there may be limits on the amount that can be possessed, cultivated, or distributed, and regulations can vary across states.

While marijuana laws are rapidly evolving, it remains illegal at the federal level in the US, classified as a Schedule I drug with a high potential for abuse and no accepted medical use. However, federal reform is a topic of ongoing discussion and review.

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