PRC Resources

PRC in the News

Fact Sheet: Preemption & Policymaking

November 2018

Health and safety problems resulting from alcohol use are a concern for communities everywhere. There are a variety of very effective policy strategies shown by research to reduce these problems.  But what power do jurisdictions have in establishing these policies? One issue that frequently arises when a community attempts to establish its own regulations is legal preemption.

Preemption is a legal principle that can affect policymaking significantly, especially at the local level. Although complex in practice, preemption in its simplest form addresses when the laws of the federal level control the laws of states, and when the laws of the state control the laws of local governments. In other words, preemption has the capacity to limit regulation by state or local governments. This Fact Sheet provides advocates and policymakers with the basics about preemption and its import when working to establish new laws.     

  1. What is preemption?

    Preemption is the legal principle that one jurisdiction’s law can be invalidated by that of a higher level of government -- that is, state and local law can be invalidated by federal law, or local law by state law. 

    The original basis for preemption is the Supremacy Clause of the U.S. Constitution, which declares federal law the supreme law of the land. 

  2. Why is preemption a concern when policymaking?
  3. Preemption is used by a higher level of government to establish uniform policy on a topic and can limit the laws that a lower level of government may want to establish on that topic. Preemption may be broad or narrow. For example, a state law may prohibit a local government from establishing any laws on a specific topic or just some parts.

    Preemption may also establish a floor or a ceiling on the laws that may be enacted. Floor preemption occurs when a higher level of government establishes a policy on a topic and explicitly permits lower levels of government to establish more rigorous requirements. For example, a state may specify minimum distance between liquor sellers and schools, churches, colleges or universities, playgrounds or other designated places. But it may also allow localities to establish even greater distances if they choose

    Ceiling preemption occurs when a higher level of government establishes a policy on a topic and prohibits lower levels of government from establishing any different policies on it. Preemption that establishes a ceiling is typically what people mean when they speak about preemption. In the example above, once the state has established a minimum distance between liquor sellers and designated places such as schools, it might prohibit localities from establishing stricter regulations on distances. These ceiling preemption laws can have the greatest effect on policymaking, especially at the local level, because it can limit the types of laws that lower levels of government may enact.     

  4. Is preemption always a bad?

    Preemption is not inherently good or bad. Rather, it is a matter of context and perspective that dictates whether a preemption provision is either positive or negative. For example, in public health, uniform state-level policies on vaccination and quarantine can be “good” when speaking about communicable disease, while prohibitions on local outdoor smoking bans can be “bad” when a community wants to reduce the harms associated with second-hand smoke.

  5. What forms can preemption take?

    Preemption typically takes one of two forms: express or implied. Express preemption is the simplest to identify and occurs when a policy explicitly states the degree to which a lower level of government may establish other laws on a topic.

    Implied preemption is more difficult to identify and takes one of two forms: conflict or field. Conflict preemption occurs when it is impossible to comply with laws on a topic enacted by differing levels of government because they conflict with each other, or a law at one level interferes with the objective of a law enacted at a higher level of government. For example, consider state laws establishing drinking age, it would be impossible to comply with both a state law setting the age at 21 and a local policy that established an older or younger drinking age.

    Field preemption occurs when a higher level has so thoroughly legislated in an area of law that it is clear (to the courts) that there is no room left for lower levels of government to do so. Examples of field preemption include nuclear power plant safety, immigration, and labor relations, all areas of policy where the federal government has a strong interest in regulating uniformly across the country and has left little room for states and cities to regulate.

  6. How to determine if a policy is preempted?

    It is important that localities not assume that preemption is in force when seeking to establish a new policy, especially at the local level. If it is seen as beneficial to establish the policy, it is important to determine whether that is legally possible.

    The first step to determine whether a given policy may be preempted by a higher level of government is to determine whether any other similarly situated governmental bodies already have a similar law. For example, when seeking to establish a local social host ordinance, it is helpful to determine if another city or county in the state already has one.

    In the absence of a similar policy, the next step is to search state and/or federal law for any express statements of preemption or any provisions establishing a floor on the topic. Finally, a public health attorney or organization that provides technical assistance on legal issues should be consulted to help navigate the legal complexities when seeking to establish any new policy.1

  7. Can preemption be overcome?

    Yes. In some instances, one source of law may preempt action on a certain topic while a competing area of law may grant an opportunity to enact policy that addresses the topic.

    An example of a lower level of government regulation on a topic that appears on its face to be preempted can be found in the case of Deemed Approved Ordinances in California.  Although, California’s Constitution broadly preempts local government from regulating sales activities at alcohol retail establishments, state law also holds that retail alcohol licenses shall not be issued contrary to valid zoning ordinances. California Courts have interpreted this delegation of authority to local governments broadly in recognition of their important role regulating land use and protecting public safety. Relying on these powers, local governments are able to impose regulations on alcohol retailers that address aspects of their sales activities -  despite laws suggesting that all action on this topic was preempted by the state.  

Additional information about of preemption:

Mosher, James F., Carol Cannon, and Ryan Treffers. "Reducing community alcohol problems associated with alcohol sales: The case of deemed approved ordinances in California." Report prepared for the Ventura County Behavioral Health Department, Alcohol and Drug Programs Prevention Services. Contract 5891 (2009).

Mosher, James F., and Ryan D. Treffers. "State pre-emption, local control, and alcohol retail outlet density regulation." American journal of preventive medicine 44, no. 4 (2013): 399-405.

The Network for Public Health Law provides opportunities for technical assistance. Information is available at:  

# # #

PIRE is an independent, nonprofit organization merging scientific knowledge and proven practice to create solutions that improve the health, safety and well-being of individuals, communities, and nations around the world.

The Prevention Research Center (PRC) of PIRE is one of 16 centers sponsored by the National Institute on Alcohol Abuse and Alcoholism (NIAAA), of the National Institutes of Health, and is the only one that specializes in prevention. PRC's focus is on conducting research to better understand the social and physical environments that influence individual behavior that lead to alcohol and drug misuse.

The Resource Link for Community Action provides information and practical guidance to state and community agencies and organizations, policy makers, and members of the general public who are interested in combating alcohol and other drug abuse and misuse.

If you would like more information about this topic, please call Sue Thomas at 831.429.4084 or email her at