Sanctuary cities limit local cooperation with federal immigration enforcement

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.

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.

Sharp partisan divides shape how Americans view immigration enforcement

A January 2026 survey shows large party gaps: Both sides broadly support recording arrests, but Democrats are much more likely than Republicans to support sharing officer locations and to oppose profiling, masked officers, and neighborhood-based enforcement.

Immigration and Customs Enforcement handles immigration enforcement within the interior of the US

ICE operates inside the United States, enforcing immigration laws through investigations, arrests, detention, and deportation of individuals residing in the country illegally. This page provides an overview of the agency's mission, structure, and internal enforcement operations.

The 2025 budget bill significantly increased ICE's budget and role in federal law enforcement

The 2025 'Big Beautiful Bill' allocated $170B to immigration and border enforcement for use through 2029. ICE's nearly $100B share includes substantial increases in detention capacity and operational scope. The increased funding will make ICE the most heavily funded federal law enforcement agency.

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.

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 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.

Issues of ICE conduct span multiple Republican and Democratic administrations

Complaints of abuse and harsh treatment increased as detentions and deportations of undocumented immigrants reached record levels during former President Barack Obama's first term. Frontline investigated the causes of these claims in 2011 and found that these issues cross party lines.

The Immigration and Customs Enforcement agency was created in the aftermath of the 9/11 terrorist attacks.

Some California cities outsource their public services entirely to the county

Southern California's "contract cities" incorporate as municipalities but pay Los Angeles County for police, fire, and other services rather than running their own departments—a cost-saving model common across the region.

The Department of Homeland Security manages America's border and immigration enforcement

DHS serves as the umbrella agency managing immigration enforcement, border security, and related public safety responsibilities. Learn more about the department's budget, strategic initiatives, organizational history, and coordination of multiple agencies.

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.

Watch the DOJ attempt to reform a local police department in 2016

This report examines federal oversight of Newark's police department as the DOJ enforces reforms following its investigation into civil rights violations, highlighting the challenges of reforming local policing through federal intervention.

Studies show immigrants commit crimes at lower rates than native-born Americans

Research examining incarceration records and crime data generally finds that immigrants—including undocumented individuals—have lower crime and incarceration rates than US-born citizens, though measurement is limited by gaps in national data on immigration status.

Cities bore the brunt of the migrant surge in the 2020s

During the 2022-24 migration surge, cities such as New York, Chicago, and Denver faced shelter overcrowding, strained public services, and housing shortages—while the upfront costs fell almost entirely to states and cities.

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.

As of 2025, there are no federal laws involving privacy and smart city technologies

Advancements in cloud technology and artificial intelligence allow cities to capture, store, and analyze more information than ever before. Experts warn that the unhindered ability to collect and use this data may infringe on residents' rights and endanger them if the data gets into the hands of malicious parties.

Trump's 2025 asylum suspension departed from a policy framework in place since 1980

In January 2025, President Trump issued an executive order suspending the asylum program and halting application processing at the southern border. This represents a departure from recent American asylum policy traditions and international humanitarian commitments.

Policies related to the coronavirus pandemic inadvertently increased illegal border crossings

A pandemic-era public health measure called Title 42—intended to seal the border by expelling migrants immediately—backfired. Because expulsions carried no legal consequences, migrants simply tried again, driving illegal crossings to a peak of over 370,000 people in December 2023.

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 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.

Smart cities support interdepartmental goals by facilitating shared infrastructure

Instead of working in isolation, municipal departments can share data, such as lighting and telecom needs, seamlessly and collaborate to solve larger-scale problems together. Integrating public feedback systems can further improve city services and sustainability.

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

Courts generally side with state law when it conflicts with a local ordinance. Whether the contradiction is explicitly stated or merely implied by the two laws, state authority typically prevails.

Immigration courts are part of the DOJ, not the judicial branch

Unlike federal courts, immigration courts operate under the DOJ's Executive Office for Immigration Review—meaning immigration judges are DOJ employees, not independent judicial officers, and their decisions can be reviewed and overturned by the attorney general.

Some argue that restricting illegal immigration would raise wages for lower-income American workers

The Heritage Foundation argues that illegal immigrants' willingness to work for below-market wages suppresses wages for low-skilled American workers—and that reducing illegal immigration would increase wages and job opportunities, particularly for workers without a college degree.

Poems and stories inscribed on the walls of a US immigration island

What Ellis Island was to the East Coast, Angel Island was to the West. Just off the coast of San Francisco, this processing center became a detention center for those targeted by exclusionary immigration laws. Click here to read some of the stories left by the detained.

Hear from those who reported on the ground in Minneapolis amid immigration raids

In this podcast episode, journalists reporting from Minneapolis describe ICE enforcement actions, street protests, and community fallout—offering firsthand accounts of how immigration crackdowns are unfolding in the Midwestern city.

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.

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.

Certain government assistance programs are available to green-card holders

Federal programs such as Medicaid and SNAP are often available to US green-card holders, but that's not typically the case for people with other immigration statuses in the US, like DACA recipients, asylum applicants, and unauthorized immigrants.

Before 1965, US immigration law relied on nationality-based bans and quotas.

Advocates for restricting birthright citizenship argue that some parents aren't 'fully subject to US jurisdiction'

Proponents of limiting birthright citizenship claim that undocumented immigrants and temporary visa holders do not meet the 14th Amendment's "subject to the jurisdiction" requirement, arguing their allegiance remains with another country.

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.

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.

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%).

The federal government sent roughly $1.1T to state and local governments in 2024

Federal grants support a large portion of state and local budgets, funding Medicaid, infrastructure, education, and housing. In FY 2024, these transfers made up about 16% of total federal spending.

Special districts are a form of local government focused on a single purpose

Unlike cities or counties, which provide a wide range of services, special districts are created to perform a single function, such as water, transit, or mosquito control. They are governed by appointed boards, have independent taxing authority, and now number nearly 40,000 across the US.

Many local governments also struggle to rein in their spending.

The Supreme Court has greatly expanded executive power in recent years

In Trump v. United States, the court ruled that a former president enjoys absolute immunity for "official acts" in his constitutional core powers. In Trump v. CASA, Inc., the court limited federal courts' ability to block executive enforcement through nationwide injunctions—decisions that shifted power toward the executive branch.

Listen to Palantir CEO Alex Karp explain how ICE uses the company's services

Alex Karp is well-known for being outspoken both about his own beliefs and about the role of Palantir in protecting Western civilization. Karp has said that while supporting government institutions doesn't always mean supporting every policy or decision those institutions make, not allowing Immigration and Customs Enforcement to access Palantir's services would go against the company's central mission of supporting Western democracy.

The reservation system gives tribes limited self-governance while keeping them under federal control.

Visa overstays account for nearly 40% of illegal US entries

In fiscal year 2023, approximately 510,000 people overstayed their visas, while 860,000 crossed the border illegally, meaning overstays accounted for 37% of the total number of new unauthorized arrivals. This represents a shift from 2007 to 2018, when overstays outnumbered border crossings, to 2019, when illegal crossings surged again.

States have stepped in to keep national parks open during shutdowns

National parks typically close during federal shutdowns, but in 2023, Arizona and Utah planned to use state funds to keep parks open—highlighting how shutdowns can disrupt tourism and local economies.

An interactive investigation into drugs and migration in San Francisco

This interactive article investigates the connection between the boom in US migration from Honduras and drug dealing in San Francisco. A high concentration of Hondurans are fleeing Siria Valley, where poverty and national murder rates run high...

Both parties largely agree that America's immigration system is broken

This three‑part podcast series traces America's immigration system origins, revealing how historically celebrated Ellis Island-era policies evolved into today's fractured, fact‑starved debate—shedding light on economic, cultural, and political forces shaping the current dysfunction.

DACA provides temporary protection for undocumented youth brought to America as children

Created by executive order during the Obama administration, the Deferred Action for Childhood Arrivals policy provides temporary deportation protection and work authorization for undocumented individuals brought to the US as children. Explore the history and ongoing political debates surrounding DACA and citizenship pathways.

Federal systems are a minority among the United Nations' 193 members

Of the United Nations' 193 member countries, roughly two dozen use a federal system, dividing power constitutionally between national and subnational governments. This group includes the United States, India, Canada, Germany, and more. The video walks through examples of how these states operate.

Federalist 51 argues that liberty could be protected within the national government

In Federalist 51, James Madison wrote that separating powers and pitting their ambitions against one another would restrain federal overreach from within, reducing reliance on state resistance as the sole check on national authority.

The DEA enforces federal drug laws under the Department of Justice

Established in 1973, the Drug Enforcement Administration directs federal efforts to fight illegal drug trafficking, oversee controlled substances, and dismantle large narcotics networks both within the United States and internationally.