Arizona v. United States
Headline: High court blocks key parts of Arizona’s 2010 immigration law, striking down state criminal penalties and warrantless-arrest rules while allowing officers to check immigration status in many stops subject to state review.
Holding: The Court held three provisions—criminal penalties for registration failures and unauthorized work, and broad warrantless-arrest authority—are preempted by federal immigration law, while it refused to enjoin the routine status-check requirement pending state interpretation.
- Blocks Arizona from enforcing registration, employment, and warrantless-removal provisions.
- Allows officers to check immigration status during lawful stops, subject to state-court interpretation.
- Reaffirms federal primacy over removal and arrest decisions in immigration enforcement.
Summary
Background
The State of Arizona passed S. B. 1070 in 2010 to address the large number of people living in the State without federal authorization. Four parts of the law were challenged by the Federal Government: making failure to carry federal registration documents a state misdemeanor (§3); making it a state misdemeanor for unauthorized aliens to seek or do work (§5(C)); authorizing state and local officers to make warrantless arrests when they believe a person committed an offense that makes them removable (§6); and requiring officers, in some stops, to try to check a person’s immigration status with federal authorities (§2(B)). A federal district court and the Ninth Circuit enjoined the provisions, and the United States asked the Supreme Court to decide whether federal law displaces these state rules.
Reasoning
The Court focused on whether federal immigration law either occupies the field or conflicts with the Arizona measures. The majority explained that federal immigration law is comprehensive. It held §3 preempted because Congress has a unified alien-registration system; §5(C) preempted because Congress chose not to impose criminal penalties directly on unauthorized workers in the federal scheme; and §6 preempted because unilateral state arrest authority would interfere with the federal removal process. By contrast, the Court refused to enjoin §2(B) because the provision can be read to allow status checks during lawful detentions and needs state-court construction before finding a conflict.
Real world impact
For now, Arizona cannot use its state courts or police to prosecute registration failures, criminalize working by unauthorized aliens, or broadly make warrantless arrests based on removability. State and local officers may still consult federal databases to verify status during lawful stops, but how §2(B) will operate in practice depends on later state-court and factual developments. Federal immigration agencies retain primary control over removal decisions.
Dissents or concurrances
Three Justices (Scalia, Thomas, and Alito) filed opinions disagreeing in part, arguing the majority gives too little authority to States to protect borders; Justice Kagan did not participate.
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