## Facts

- Arizona enacted the Legal Arizona Workers Act (LAWA), authorizing (and sometimes requiring) state-court suspension or revocation of business licenses for employers that knowingly or intentionally employ unauthorized aliens.
- LAWA also required all Arizona employers to use E-Verify, a federal internet-based system that checks work authorization status.
- The federal Immigration Reform and Control Act of 1986 (IRCA) prohibits hiring unauthorized aliens and provides federal civil and criminal penalties.
- IRCA contains an express preemption clause barring state “civil or criminal sanctions (other than through licensing and similar laws)” on employers of unauthorized aliens.
- Congress created E-Verify as an experimental program under the Illegal Immigration Reform and Immigrant Responsibility Act of 1996.
- The Chamber of Commerce and other organizations filed a pre-enforcement federal suit against Arizona officials, asserting that LAWA’s licensing sanctions were expressly and impliedly preempted and that LAWA’s mandatory E-Verify requirement was impliedly preempted.
- The district court upheld LAWA, and the Ninth Circuit affirmed.

## Issues

1. Whether IRCA’s express preemption clause invalidates Arizona’s law authorizing suspension or revocation of business licenses for employing unauthorized aliens.
2. Whether Arizona’s requirement that employers use E-Verify is impliedly preempted because federal law makes E-Verify participation voluntary.

## Decision

- The Supreme Court affirmed and upheld LAWA in a 5–3 decision.
- LAWA’s license suspension and revocation scheme was not expressly preempted because it operated “through licensing and similar laws” within IRCA’s savings clause.
- LAWA was not impliedly preempted as a conflicting or obstructive state regime because it relied on federal determinations of unauthorized status and tracked federal verification mechanisms, including a good-faith safe harbor tied to the federal I-9 process.
- LAWA’s E-Verify mandate was not impliedly preempted because federal law did not bar state E-Verify requirements and the mandate did not conflict with federal objectives.
- Justice Thomas concurred in the judgment on a primarily textual reading of IRCA’s savings clause.
- Justice Breyer (joined by Justice Ginsburg) and Justice Sotomayor dissented; Justice Kagan did not participate.

## Legal Principles

- IRCA expressly preempts state “civil or criminal sanctions” against employers of unauthorized aliens except sanctions imposed “through licensing and similar laws.”
- State measures conditioning the continued validity of business licenses can fall within IRCA’s licensing savings clause when consistent with the federal understanding of “license.”
- A state employer-sanctions law is less likely to be conflict-preempted where state enforcement turns on federal determinations of whether a worker is unauthorized.
- A state E-Verify mandate is not impliedly preempted merely because federal law treats E-Verify as voluntary, absent a congressional restriction on state participation requirements.

## Conclusion

The Court held that IRCA permits Arizona to impose employer sanctions through business-licensing consequences and does not bar Arizona from requiring employers to use E-Verify, rejecting both express preemption (as to licensing) and implied preemption claims.


Chamber of Commerce of the U.S. v. Whiting, 563 U.S. 582 (2011)