Arizona v. United States

2012-06-25

Headline: Court blocks three Arizona immigration measures — state penalties for failing to carry registration, banning unauthorized work, and broad warrantless arrests — but allows the status-check rule to be reviewed by state courts.

Holding: The Court held that federal immigration law pre-empts Arizona’s state misdemeanor for failing to carry registration (§3), the state crime for unauthorized work (§5(C)), and the warrantless-arrest provision (§6), but did not enjoin the status-check rule (§2(B)) pending state-court interpretation.

Real World Impact:

Blocks Arizona from criminally punishing failure to carry federal registration papers.
Prevents Arizona from criminalizing unauthorized workers in place of federal enforcement.
Leaves officers able to seek ICE status checks in some lawful stops, subject to limits.

Topics: immigration enforcement, state vs federal power, police stops, unauthorized work

Summary

Background

Arizona passed a 2010 law aimed at reducing unlawful immigration. The United States sued, asking federal courts to stop four parts of the law from taking effect: (1) a state crime for not carrying federal alien-registration papers (§3), (2) a state crime for unauthorized aliens who seek or do work (§5(C)), (3) authority for state officers to make warrantless arrests when they believe someone is removable (§6), and (4) a rule that officers must try to verify immigration status during some stops or arrests (§2(B)). Lower courts issued a preliminary injunction against all four provisions, and the case came to the High Court.

Reasoning

The Court emphasized that the federal government has broad authority over immigration and that Congress has created detailed federal rules. It held that federal law occupies the field of alien registration, so Arizona may not add its own criminal penalties for failing to carry registration (§3). It found §5(C) conflicts with the federal employment enforcement framework (IRCA), which deliberately left certain employee-side penalties out, so the state ban on unauthorized work is an obstacle. Section 6 was invalidated because allowing widespread, unilateral warrantless arrests based on possible removability would undermine the federal removal system and the Federal Government’s discretion.

Real world impact

The ruling prevents Arizona from enforcing three of the law’s central criminal tools, preserving federal control over registration, employer sanctions, and removal procedures. The Court did not enjoin §2(B) because its meaning and enforcement remain unclear; state courts may interpret it, and the provision might be applied without conflicting with federal law. The case was sent back for further proceedings consistent with this opinion.

Dissents or concurrances

Several Justices disagreed in part, arguing the States retain broader sovereign powers to protect their borders and that the Arizona provisions should stand. They emphasized traditional state authority over employment and arrests and urged deference to state policing choices.