1. United States
2. Mass.
3. Letter

The Supremacy Clause of the United States Constitution establishes that valid federal law is the “supreme Law of the Land.” When federal and state law conflict, federal law prevails. It does not require states to finance, facilitate, or expand federal enforcement infrastructure. Under long-standing Supreme Court precedent, the federal government may not “commandeer” state governments to carry out federal programs. This anti-commandeering doctrine protects state sovereignty by ensuring that federal authority does not become a mandate for state participation. Immigration and Customs Enforcement (ICE) is a federal agency. If ICE seeks to expand detention capacity, that responsibility lies with Congress and the federal executive branch. States are not obligated to: • Provide land or public facilities • Enter into detention contracts • Allocate state funds • Grant discretionary permits or zoning approvals • Supply state or local personnel The Supremacy Clause prevents states from obstructing lawful federal operations. It does not compel them to subsidize them. Recent events demonstrate that state and local officials retain meaningful leverage. In New Hampshire, Governor Kelly Ayotte engaged directly with federal officials after concerns were raised about a proposed ICE detention facility in Merrimack. The federal government ultimately withdrew the plan. In Maryland, state leaders filed suit to halt construction of a proposed ICE detention center, arguing that required environmental and procedural laws were not followed. That lawsuit does not attempt to nullify federal authority; it insists on compliance with lawful review and state consultation. National reporting has further documented that proposed ICE detention facilities in multiple states have been advanced with limited public transparency and have faced significant local opposition. When projects of this magnitude move forward without meaningful consultation, it underscores why state oversight and discretionary authority matter. This is not nullification. It is federalism in action. If a proposed ICE detention facility requires state participation — through contracts, infrastructure commitments, licensing, public safety coordination, or other discretionary approvals — you have both the authority and the responsibility to determine whether that participation serves the public interest. I urge you to: • Deny new or expanded detention contracts involving state resources. • Refuse discretionary approvals that enable expansion without full transparency and lawful review. • Ensure that state land, funds, and personnel are not used to enlarge federal detention capacity without clear consent and oversight. Federal authority is supreme within its constitutional sphere. But states are not required to build the machinery of federal detention. Respecting the Supremacy Clause means respecting its limits.