Rudd Center for Food Policy and Obesity


Preemption refers to the ability of a higher level of government to restrict certain actions by a lower level of government. The U.S. Constitution's Supremacy Clause explains that federal law is the supreme law of land, which means that federal legislation or regulation can preempt state and local law. Local laws can additionally be preempted by state-level legislation or regulation. Preemption can significantly impact the ability of those in lower jurisdictions to enact public health laws. Because public health problems are not evenly distributed throughout the population, states and localities may want to enact laws or regulations that respond to their particular circumstances. In 1932, Justice Brandeis put it best by saying, "It is one of the happy incidents of the federal system that a single courageous State may, if its citizens choose, serve as a laboratory, and try novel social and economic experiments without risk to the rest of the country." President Obama issued a memorandum against preemption, which explained: "Throughout our history, State and local governments have frequently protected health, safety, and the environment more aggressively than has the national Government." The purpose of the memo was "to state the general policy of my Administration that preemption of State law by executive departments and agencies should be undertaken only with full consideration of the legitimate prerogatives of the States and with a sufficient legal basis for preemption."

Learn more by reading the IOM Preemption Highlights and Preemption and Movement Building in Public Health Fact Sheet. Learn how to avoid preemption in your jurisdiction.