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emigration and immigration law, immigration, detention, habeas, federalism, preemption, fourth amendment, immigration enforcement, immigration detainer, state law, localism


The Trump administration’s aggressive immigration enforcement campaign calls on hundreds of thousands of local police officers and county sheriffs to identify and detain people suspected of violating federal civil immigration law. The immigration detainer is a key mechanism of Trump’s campaign and is on the rise. A detainer asks local law enforcement officers to hold individuals beyond the period authorized by local law so that federal immigration officials have additional time to take custody of the person. In practice, detainers attach the threat of deportation to any contact with local police. Immigrant rights advocates have challenged the use of detainers with mounting success. As the contest over detainers continues, the battle lines are shifting from federal to state law with officials now searching for authority in states’ earliest attempts to regulate local arrest authority and cooperation of local law enforcement agencies in jailing federal prisoners. This article presents the first examination of these state and territorial laws along with the historical limits they place on local law enforcement officers. By resurrecting this history, the article reveals that the laws of most states fail to authorize detainer enforcement. Rather, local immigration policing would require new and specific authority. Expanding the role of local law enforcement officers beyond their traditional constraints, however, comes at a substantial cost. Structurally, it erodes the benefits of individual liberty, political accountability, and uniformity promised by federal immigration control. Individually, it leaves the fate of an immigrant at a traffic stop to the discretion of a local officer and forces families to navigate a patchwork of local immigration policy. This article argues instead that maintaining the traditional scope of state police power better protects the safety and civil rights of immigrant communities.

Library of Congress Subject Headings

Immigrants--Government policy, Immigration enforcement, Federal-state controversies, Detainers (Criminal procedure)