State and local immigration enforcement in the U.S.

While immigration enforcement is a federal responsibility, state and local governments can also play an important role. The extent of that role has become a divisive topic in recent years, especially with the growing use of U.S. Immigration and Customs Enforcement (ICE) partnerships with local law enforcement and the debate over so-called “sanctuary cities.” In this article, we’ll explore how immigration enforcement works at the state and local levels—and how states across the country vary in their approaches.

What is the 287(g) program?

Section 287(g) of the Immigration and Nationality Act allows ICE to partner with local law enforcement agencies. Under this program, trained local officers can perform certain immigration enforcement functions, such as checking an individual’s immigration status or initiating deportation proceedings. ICE maintains a list of current 287(g) agreements, which includes jail-based and task force models. Learn more about the 287(g) program here.

Supporters say the program enhances cooperation and keeps communities safe by identifying undocumented immigrants charged with crimes. Critics argue it erodes trust between immigrant communities and the police, making people less likely to report crimes or cooperate with investigations.

As of July 2025, twelve law enforcement agencies in New Hampshire participate in the 287(g) Program and perform some immigration enforcement. Learn more about the 287(g) Program in New Hampshire.

Sanctuary cities

Some cities and states have adopted “sanctuary” policies, generally limiting cooperation with federal immigration enforcement. For example, a city may prohibit local police from asking about immigration status or detaining individuals based solely on an ICE request. The term “sanctuary city” is not formally defined in law, so its meaning often varies depending on who you ask.

In early 2025, the U.S. Department of Homeland Security (DHS) published a list of over 500 so-called “sanctuary jurisdictions” it deemed noncompliant with immigration enforcement. The cities on the list could have their federal grants or contracts suspended or terminated, according to an April 28 executive order. President Trump’s targeting of sanctuary cities has received pushback from U.S. courts.

Immigration detention facilities

ICE operates or contracts with hundreds of detention facilities across the U.S. to hold individuals facing removal proceedings. These range from local jails with ICE contracts to dedicated federal detention centers. You can find a list of ICE detention facilities here.

Some have criticized the conditions in these facilities, raising concerns about oversight. Supporters of immigrant detention see it as a necessary tool for border and interior enforcement.

ICE holds immigrants at two detention facilities in New Hampshire: the Strafford County jail and the federal prison in Berlin. Learn more here.

Differences between states

States vary widely in how they approach immigration enforcement and services for immigrants. For example, some states allow undocumented immigrants to apply for driver’s licenses, while others require proof of legal status. Eligibility for state-funded benefits—such as in-state tuition or health services—also differs significantly. You can see a list of states that offer driver’s licenses to immigrants here or learn what states offer health coverage for undocumented people here.

Some states—including New Hampshire—actively support ICE cooperation, while others place limits on such partnerships. Here is a helpful map detailing how states differ on immigration enforcement.

What about busing migrants?

In recent years, some state governments have made headlines for transporting migrants—often asylum seekers—from southern border states to cities like New York, Washington D.C., or Chicago. For example, Governors Greg Abbott (R-Texas) and Doug Ducey (R-Arizona) have sent thousands of migrants to these large American cities, arguing illegal immigration is a crisis their states cannot bear alone. Proponents say the practice is necessary given overcrowded shelters and limited local resources, while critics view the moves as political stunts.

The relationship between ICE, border patrol, and state and local authorities continues to evolve as these debates play out at the state and federal levels. You can learn more about U.S. immigration enforcement by reviewing the resources on ICE’s website.