When state and local laws conflict, state law almost always prevails

The powers of local government are rooted in state law, not the Constitution

Unlike the federal government or the states, local governments have no constitutional standing—they exist only because state law allows them to. A state legislature can redraw a city's boundaries, strip its powers, or dissolve it entirely.

States are increasingly using preemption laws to override local decisions

Preemption laws enable state legislatures to prevent cities and counties from enacting their own rules on issues like minimum wage, gun control, and housing. Their use has increased significantly in recent years.

The supremacy clause establishes federal law as the highest authority

The supremacy clause states that the United States Constitution and federal laws enacted under it supersede conflicting state laws, ensuring national authority prevails when federal and state governments disagree.

Two doctrines of local governance determine how much power cities actually have

Under what is known as "Dillon's Rule," local governments can only exercise powers explicitly granted by the state. Under "home rule," cities have broader self-governing authority—but the balance between the two depends entirely on state law.

Courts referee federalism disputes between Congress and the states

Modern federalism is primarily worked out through litigation. The Supreme Court decides disputes in written opinions that explain when federal law preempts state authority, how far Congress's powers extend, and when states may resist.

In the US, any court can rule on constitutionality—unlike in most other countries

In the American system, known as diffuse judicial review, federal and state courts at every level may assess whether laws comply with the Constitution, and their decisions are ultimately reviewable by the Supreme Court. Many other democracies, by contrast, reserve constitutional review to specialized constitutional courts.

Sanctuary cities limit local cooperation with federal immigration enforcement

Sanctuary cities limit how local agencies help ICE—such as restricting detainers, jail transfers, or data sharing—while still enforcing criminal law, leaving immigration enforcement mostly to federal authorities.

Opposing policies over immigration and sanctuary cities define the contemporary debate over federalism

Disputes between the federal government, Republican-controlled states, and Democratic-controlled cities over immigration enforcement and sanctuary policies have become a central flash point in modern federalism. These conflicts will shape the future of state autonomy, federal authority, and the enforcement of national policy across jurisdictions.

Deputy sheriffs and city police have different legal authority and chains of command

Sheriffs are elected officials at the county level, and their deputies usually patrol unincorporated areas and manage county jails. City police are hired by local government authorities and operate within city limits under a different chain of command.

The 10th Amendment affirms that most undelegated powers remain with the states

Adopted to reassure skeptics of an overly powerful federal government, the amendment was meant to curb federal overreach and preserve state control over most everyday governance decisions.

State and local governments fund very different services

Local governments allocate 39% of their spending to K-12 education, while states allocate less than 1% directly—although much of local education funding actually comes from state and federal grants to local communities. States instead allocate their budgets to public welfare and health programs (45%) and higher education (15%).

States are constitutionally mandated to draw their own congressional districts

Under Article I, Section 4 of the US Constitution, state legislatures possess the authority to determine how congressional districts are drawn. However, Congress retains the power to alter these rules if it chooses to.

Immigration enforcement shows how federalism plays out on the ground

In recent years, federalism has shifted from allowing policy diversity across states to open conflict, with states and the federal government increasingly trying to impose their preferences on one another over issues like abortion, voting, immigration, and public health.

Federalism creates tension between national and state power by design

Federalism assigns authority so that neither the national government nor the states entirely dominate the other or the people they govern. By creating overlapping claims of power, the system makes negotiation, conflict, and compromise a permanent feature rather than a failure.

Thomas Jefferson and John Marshall clashed over national power and states' rights

Distant cousins Jefferson and Marshall advanced opposing constitutional visions—Jefferson favoring states' rights and local majorities, while Marshall defended broad federal authority and judicial review. Through decisions such as McCulloch v. Maryland, Marshall advanced national supremacy over state resistance.

Each state has its own regulations regarding marriage

Some states don’t even require a ceremony or license, opting to allow “common law” marriages. Prenuptial agreements and other legal matters will likely require an attorney’s help. And marriages can offer benefits, like tax breaks.

Police spending is one of the largest budget items for local governments

Local governments finance most of the costs for police in the US. Total state and local criminal justice spending—covering police, courts, and corrections—reaches hundreds of billions of dollars annually.

The nullification crisis tested whether states could defy federal law

In the 1830s, South Carolina declared federal tariffs void within its borders. President Andrew Jackson threatened military force, Congress passed a compromise tariff, and the episode ended with federal authority prevailing over state nullification.

Read the majority opinion that established judicial review

In his opinion in Marbury v. Madison, Chief Justice John Marshall argued that a written constitution is "paramount law" and that courts must refuse to enforce statutes that conflict with it. He declared that "it is emphatically the province and duty of the Judicial Department to say what the law is."

The Supreme Court has never definitively settled federal war powers

Despite more than two centuries of conflict over war powers, the Supreme Court has consistently avoided defining the precise boundary between congressional and executive authority, leaving that boundary to be contested by the political branches.

Gibbons v. Ogden expanded federal power over interstate commerce

In 1824, the Supreme Court unanimously invalidated a New York steamboat monopoly, ruling that navigation between states constitutes interstate commerce. Chief Justice John Marshall held that Congress has authority over such commerce and that conflicting state laws are void under the supremacy clause.

John Marshall advanced federal supremacy and judicial review

Marshall's jurisprudence emphasized that the Constitution is the supreme law of the land, enforceable by an independent judiciary. Through his court's decisions, he affirmed judicial review, broad implied powers for Congress, and federal authority to override conflicting state laws.

Supreme Court Justice Louis Brandeis once called states 'laboratories of democracy'

Louis Brandeis argued that federalism allows states to experiment with new policies without committing the entire nation, thereby allowing successful ideas to spread while limiting the risks of failure.

An adultery and poisoning case examined whether federal treaty power supersedes state law

This Radiolab podcast unpacks Bond v. United States, where a local love-triangle assault became a federal case under an international treaty—forcing the Supreme Court to confront a founding question: How far can federal power reach into crimes traditionally handled by the states?

Explore the nearly 1,000 laws, regulations, and provisions the court has held unconstitutional since Marbury v. Madison

Over more than two centuries, the Supreme Court has struck down nearly 1,000 federal, state, and local measures—exercising its authority to invalidate laws that conflict with the Constitution and shaping civil rights, the separation of powers, and the scope of government authority.

The Tenth Amendment reserves all powers not granted to the federal government to the states or the people

Any powers not delegated to the federal government by the Constitution are reserved to the states or to the people. It has been cited in legal battles over healthcare, marijuana, and environmental regulation.

Local governments coordinate across jurisdictions through regional councils and planning bodies

Many local governments are part of Councils of Governments or Metropolitan Planning Organizations—regional entities that coordinate transportation, land use, and other shared priorities across city and county boundaries. Federal law mandates their establishment in any metro area with a population over 50,000.

See how local, state, and federal governments divide the cost of public services

Federal, state, and local governments share responsibility for funding public services. Education, roads, and social programs are funded through a complicated mix of taxes and intergovernmental transfers.

McCulloch v. Maryland upheld implied powers and blocked states from taxing the federal government

In 1819, McCulloch v. Maryland confirmed that Congress may use implied powers under the necessary and proper clause and ruled that states cannot tax federal institutions, reaffirming the supremacy of the federal government within its constitutionally delegated powers.

Youngstown Sheet & Tube Co. v. Sawyer established the framework courts use to evaluate presidential war powers

When Truman seized US steel mills during the Korean War, the Supreme Court ruled that he had overstepped his authority. Justice Jackson's concurring opinion held that presidential power is strongest when Congress authorizes action, uncertain when Congress is silent, and weakest when Congress explicitly refuses authorization.

Constitutional originalism and living constitutionalism are the 2 main theories of interpretation

Hear from experts about originalism—the view that the Constitution should be interpreted according to its original public meaning—alongside its main counter-ideology, living constitutionalism, which argues that the document's meaning should evolve with changing social and legal norms.

Many local governments also struggle to rein in their spending.

Parliament is the supreme legal authority under the UK's constitutional system

The principle of "parliamentary sovereignty" holds that the UK Parliament can make or repeal any law, and that courts cannot invalidate its legislation. Judicial bodies can reshape governance, but parliamentary laws remain legally supreme.

American local government comes in five distinct forms

Counties, municipalities, townships, special districts, and school districts are each created for a different purpose, operating under different rules, and answerable to the state in different ways. Special districts, the least known of the group, are created for specific purposes, such as transit or fire protection.

Consolidated city-county governments merge two layers of local government into one

A city-county consolidation removes a layer of local government by merging a municipality with its surrounding county. Examples include Jacksonville-Duval County, Louisville-Jefferson County, and San Francisco, all of which operate as both cities and counties.

The separation of powers is a pivotal component of the US Constitution

Explore how the three branches interact through the Supreme Court case of US v. Alvarez. The Supreme Court first struck down a law, then Congress and the president later revised it—illustrating how judicial review can reshape legislation and executive action.

Tribal courts handle justice on reservations, but face strict limits on whom they can prosecute

Reservation-based courts handle civil and criminal cases, but federal law sharply limits their authority over non-tribal members. As a result, non-Native individuals who commit crimes on reservations often fall outside tribal jurisdiction, creating potential gaps in accountability.

Every single American state constitution references God or the divine, though the federal Constitution does not.

Presidents from both parties have resisted the authority of the War Powers Act

Presidents from both parties have treated the War Powers Resolution as voluntary, framing compliance as seeking "support" rather than "permission." Courts have declined to rule on the law's constitutionality each time a related case was brought before them.

Illinois has more local governments than any other state

As of 2022, there were a reported total of 90,837 local government units across the US. Illinois had the highest number with 6,930, followed by Texas with 5,533. Explore all the data from the 2022 Census of Governments, which takes place every five years.

Zoning laws determine what can be built—and where—in every American community

Local governments use zoning to regulate land use. About 75% of residentially zoned land in American cities is designated for single-family homes only—a restriction that some experts blame for increasing housing costs and reducing affordability.

Employment Division v. Smith (1990) reaffirmed the Reynolds decision that the law applies to everyone, regardless of faith

The Supreme Court ruled that the government does not have to grant religious exemptions from laws that apply to everyone. The case involved Native American church members fired for using peyote in a religious ceremony.

Distinguishing between scientific theories and laws, and why both are on equal footing

Scientific laws describe outcomes of specific conditions, and scientific theories explain why those outcomes occur. Both are supported by observational and experimental data and can each inform one another, but neither can become the other. Instead, additional data can improve each towards more accurate descriptions and explanations of reality.

Colonial self-rule fostered strong autonomy and distrust of centralized power

American colonies were governed through a patchwork of different systems, ranging from Crown-run to locally controlled. Broad local autonomy—often followed by sudden imperial crackdowns—taught colonial leaders to prize home rule and distrust distant centralized power, attitudes that later informed US federalism.

Presidents can veto laws—and Congress can override them

A president may veto legislation passed by Congress, but a two-thirds vote in both the House and Senate can override it. For most presidents, only a small share of their vetoes have been successfully overturned.

No school has lost federal funding because of a Title IX violation

While the law threatens the suspension of federal funds for schools violating the requirements of the law, it has yet to happen. Instead, the Office for Civil Rights has deemed schools working to correct the issues conditionally compliant.

The Supreme Court limited federal judges' power to issue nationwide injunctions in 2025

In a 2025 decision arising from litigation over a presidential order on birthright citizenship, the Supreme Court held that individual federal judges may not nationwide block executive policies—curbing the use of sweeping injunctions and reshaping how constitutional challenges proceed through the courts.

Fire districts and fire departments are governed differently

A fire department is usually a municipal agency under the control of city or county authorities. In contrast, a fire district functions as an independent special district with its own elected board, separate budget, and taxing authority.

A legal scholar argues that the existing war powers framework may collapse in the event of a major power conflict

The legal tests presidents have used to avoid seeking congressional authorization were designed for weaker adversaries. This piece argues that those tests fail against similarly armed competitors, where even limited strikes risk significant escalation, potentially triggering a constitutional crisis over who has the authority to respond.

A court designed to be the least powerful branch of government became one of the most influential institutions in America.