Can a City Refuse to Enforce a National Law? Limits of Who Must Do What

The label covers a range of policies that share a common feature, which is declining to devote local resources to enforcing immigration law that the local authority has no independent duty to enforce. Typical measures include refusing to hold a person in custody beyond their release date at the request of federal officers without a judicial warrant, declining to ask about immigration status during ordinary policing or when providing services, and limiting what information is shared with federal agencies. What such policies do not do is prevent federal officers from operating in the jurisdiction or grant anyone immunity from federal law, which is a common misunderstanding. The term is informal, has no legal definition and is applied to very different arrangements, which makes generalisations about it unreliable.

Supporters advance arguments that are largely practical rather than about immigration policy:

• •Willingness to report crime and testify falls if contact with police risks deportation, which reduces safety for everyone
• •Local budgets are spent on a federal function without reimbursement
• •Holding somebody past their release date without a judicial warrant exposes the locality to legal liability
• •Local officers are not trained in immigration law and errors have detained citizens
• •Community trust in institutions including schools and hospitals is affected
• •The locality did not choose the policy it is being asked to implement

The legal basis rests on a doctrine about the structure of divided government rather than on immigration at all. Courts in the United States have held that the national government may not compel state or local officials to administer or enforce a federal regulatory programme, a principle developed in cases concerning firearms background checks and radioactive waste and usually called the anticommandeering doctrine. It leaves the federal government free to enforce its own laws with its own officers and free to offer funds conditionally, while barring it from conscripting state machinery. That framework is why the strongest form of these policies has generally survived challenge, and why disputes have centred instead on whether funding conditions attached to grants are permissible, an area where courts have divided.

The term borrows from a much older institution with a different logic, and the comparison is instructive rather than merely etymological. Sanctuary in medieval Europe meant that a fugitive reaching a church could not be seized from it, a right recognised in law with defined procedures, time limits and in England the option of confessing and being sent into exile rather than tried. It rested on the sacredness of the place rather than on any judgement about the accusation, and it functioned as a cooling-off mechanism in a system with weak policing and strong private vengeance. It was restricted and then abolished in England in the seventeenth century. The modern usage retains the idea of a place where enforcement is withheld and rests on an entirely different basis, which is a jurisdictional argument about which government must do what.

The underlying problem is general and appears wherever authority is divided. Federal systems including Germany, Canada, Australia and India all have to allocate enforcement duties between levels and all have doctrines about what one level may require of another. European Union law operates on the opposite principle in many areas, requiring member states to enforce union law with national machinery, which is a deliberate design choice with its own difficulties. Within unitary states the question arises between central and local government over policing priorities, planning and the delivery of services. In every case the practical issue is the same, which is that the level writing a rule and the level bearing the cost of enforcing it are frequently different, and that gap produces both efficiency and conflict.

These policies decline to spend local resources on enforcing a law the locality has no independent duty to enforce, and they neither exclude federal officers nor grant immunity. The legal basis is a doctrine barring the national government from conscripting state machinery, developed in cases about firearms checks and waste. Disputes have shifted to whether funding conditions are permissible.