State Vs Federal Law: What's Allowed?

In the United States, federal law applies to all citizens, while state laws only apply to citizens within a particular state. The area of law that addresses possible conflicts between state and federal laws is referred to as the Supremacy Clause of the US Constitution, which states that federal law supersedes state law in many but not all cases. The federal government can pass a law that restricts or supersedes the effect of a state law, provided that it has authority over the subject. This means that a state can allow something that federal law prohibits, as long as it does not prevent federal authorities from enforcing their own laws.

Marijuana laws

The legal status of marijuana at the federal level is outlined in the Controlled Substances Act, which classifies marijuana as a Schedule I drug, indicating that it has a high potential for abuse and no accepted medical value. This classification places marijuana in the same category as other serious and deadly drugs, such as heroin and LSD. Under federal law, it is illegal to possess, sell, or distribute marijuana, and penalties for these offences can be severe.

However, at the state level, a growing number of states have enacted legislation to legalise marijuana, creating a patchwork of varying laws and regulations across the country. For example, in 1996, California voters approved a ballot initiative to legalise marijuana for medical use, becoming the first state to establish a medical marijuana programme. Since then, many other states have followed suit, with some also legalising the drug for recreational use. As of March 2025, marijuana laws are subject to constant change, with updates being made on a monthly basis.

The discrepancy between state and federal marijuana laws has led to legal complexities and uncertainties. While the federal government has the authority to supersede state laws under the Supremacy Clause of the US Constitution, it has largely allowed states to implement their own regulatory frameworks for marijuana. This is due to the fact that state regulatory activity does not prevent federal authorities from enforcing their own laws, and state workers are not directly involved in the cultivation or sale of marijuana. Additionally, the federal government has shown a willingness to defer to state-legalised marijuana sales as long as states provide robust regulation, as outlined in the Cole memo released by the Department of Justice in 2013.

Despite the evolving legal landscape, it is important to note that marijuana remains illegal under federal law, and individuals must comply with the specific laws and regulations of their respective states. These laws can vary widely, with different limits on factors such as the amount, form, and THC content of marijuana that is permitted. For example, in Virginia, it is illegal to use or consume cannabis while driving or being a passenger in a motor vehicle, and there are federal laws prohibiting the transportation of cannabis across state lines and the possession of cannabis during air travel. As the legal status of marijuana continues to evolve, individuals must stay informed about the specific laws and regulations in their state to ensure compliance and avoid legal repercussions.

Supremacy Clause

In the United States, the Supremacy Clause is a significant constitutional provision that establishes the supremacy of federal law over state law. It is outlined in Article VI of the US Constitution, which states that federal laws and treaties made under the authority of the United States are the "supreme Law of the Land". This clause ensures that federal authority takes precedence, and judges in every state are bound to follow it, regardless of any conflicting state laws or constitutions.

The Supremacy Clause was introduced as part of the New Jersey Plan during the Federal Convention of 1787, addressing issues with the Articles of Confederation that lacked a clear declaration of federal supremacy. The Articles of Confederation, which preceded the US Constitution, included Article XIII, stating that "Every State shall abide by the determination of the [Congress] on all questions submitted to them." However, during the Confederation era, federal statutes did not bind state courts unless state legislation implemented them.

The Supremacy Clause is essential in resolving conflicts between state and federal laws. This is particularly evident in the case of marijuana legislation, where some states have legalised medicinal or adult-use cannabis, conflicting with federal law, which classifies marijuana as a Schedule I drug. The Supremacy Clause's doctrine of preemption states that federal law supersedes state law in most cases of conflict. However, the federal government has generally taken the position that state regulatory activity in this area does not violate the Supremacy Clause, as states do not prevent federal authorities from enforcing their laws.

The Supreme Court has played a significant role in interpreting and applying the Supremacy Clause, recognising several types of preemption. Federal law can expressly preempt state law when it explicitly states so, or it can be impliedly preempted when that intent is inherent in its structure and purpose. Field preemption occurs when federal law is so pervasive that it leaves no room for state supplementation or when the federal interest is dominant. The Supreme Court has also applied the Supremacy Clause to uphold the supremacy of treaties over state law, considering them equally as "supreme law of the land" with federal statutes.

State sovereignty

In the United States, state laws only apply to citizens within a particular state, while federal law applies to all US citizens. This means that a person can act in compliance with one set of laws but be in violation of another.

The US Constitution's Supremacy Clause, found in Article VI, addresses conflicts between state and federal laws. The clause includes the doctrine of "preemption", which states that federal law supersedes state law in most cases of conflicting laws. However, for preemption to occur, the Constitution must grant the relevant power to the federal government, and the federal government must have authority over the subject matter.

While the federal government may want states to make certain things illegal, it doesn't happen automatically, and the federal government is limited in how it can make states comply. For example, in 1996, California voters decided to create an exception to their state marijuana possession law for residents with certain medical requirements, despite federal law still considering possession by those individuals illegal.

In some cases, states have ceded aspects of their sovereignty to the federal government, such as the ability to enter treaties with foreign powers. In other cases, states retain the power to make laws, but federal law prevails if there is a conflict.

The federal government can pass a law that restricts or supersedes the effect of a state law, as long as it has authority over the subject. This can effectively repeal or amend the state law. The federal government can also regulate anything that impacts commerce that crosses state lines, as per the interstate commerce clause.

Federal preemption

In the United States, federal law applies to all citizens, whereas state laws only apply to citizens within a particular state. The area of law that addresses possible conflicts between state and federal laws is generally referred to as the Supremacy Clause of the US Constitution, a key provision appearing in Article VI.

The Supremacy Clause includes the doctrine of "preemption", which states that in many (but not all) cases of conflicting laws, federal law supersedes state law. This means that a state law can be preempted by federal law if it conflicts with a federal statute or treaty. However, it's important to note that the Constitution must grant the relevant power to the federal government, and they cannot just make laws about anything.

For example, in 1996, California voters decided to create an exception to their state marijuana possession law for residents who met certain medical requirements. While the federal government still considered possession by those individuals illegal, California was not required to keep possession illegal. Marijuana is classified as a Schedule I Drug under federal law, but as more states have legalized medicinal and adult-use cannabis, the federal government has not changed its laws. The federal government has taken the position that state regulatory activity does not violate the Supremacy Clause, likely because states do not prevent federal authorities from enforcing their own laws.

In another instance, the Department of Justice released "the Cole memo" in 2013, stating that state-legalized marijuana sales remained illegal under federal law. However, the memo advised federal prosecutors to not prioritize marijuana enforcement unless states failed to provide "robust" regulation. Neither the Cole memo nor the federal laws have binding force, meaning that federal prosecutors have discretion when it comes to handling marijuana activities.

Federal enforcement

In the US, federal law applies to all citizens, whereas state laws only apply to citizens within a particular state. The area of law that addresses possible conflict between state and federal laws is referred to as the Supremacy Clause of the US Constitution, which appears in Article VI. This clause includes the doctrine of "'preemption'", which states that federal law supersedes state law in many but not all cases of conflicting laws.

The federal government can pass a law preempting a state law or restricting or superseding the effect of a state law, provided that the federal government has authority over the subject matter. This would have the effect of repealing or amending the state law. The federal government can also pass laws prohibiting actions under the Commerce Clause, which allows it to regulate anything that impacts commerce that crosses state lines.

The federal government may want states to make certain things illegal, but it doesn't happen automatically, and the federal government is limited in the ways it can make states comply. For example, in 1996, California voters decided to create an exception to their state marijuana possession law for residents with certain medical requirements, despite the fact that the federal government still considered possession by those individuals illegal.

In 2013, the Department of Justice released "the Cole memo", which stated that state-legalized marijuana sales remained illegal under federal law, but advised federal prosecutors to not prioritize marijuana enforcement unless states failed to provide "robust" regulation. However, in 2018, Attorney General Jeff Sessions rescinded that memo, leaving federal policy uncertain.

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