In 1986, Congress enacted IRCA, making it unlawful for an employer to knowingly hire unauthorized aliens, and imposing both civil and criminal sanctions for violations. The Act also expressly preempts "any State or local law imposing civil or criminal sanctions" for hiring unauthorized aliens "other than through licensing and similar laws." In 1996, Congress supplemented federal immigration laws by creating a voluntary federal program known as E-Verify. E-Verify is an internet-based system that allows an employer to verify an employee's authorization status.
Against this federal background, Arizona enacted the Legal Arizona Workers Act of 2007, which prohibits employers from knowingly or intentionally employing unauthorized aliens and enforces the prohibition by suspending or revoking a violator's licenses to operate in Arizona. The law also requires employers to use the federal E-Verify system to confirm the authorization status of employees.
The Chamber of Commerce challenged Arizona's law, arguing that it is both expressly and impliedly preempted by IRCA. The district court rejected the challenge; the Ninth Circuit affirmed; and the Supreme Court granted review.
In the portions of his opinion joined by four other justices, Chief Justice Roberts makes short work of the express-preemption argument. IRCA expressly permits states to impose sanctions "through licensing and similar laws." The Arizona law, on its face, "purports to impose sanctions through licensing laws." It defines licenses similar to how the federal Administrative Procedure Act does. And no other aspect of the Arizona law alters its licensing quality. "Arizona's licensing law falls well within the confines of the authority Congress chose to leave to the States and therefore is not expressly preempted." Regarding Arizona's requirement that employers use E-Verify, that requirement "does not conflict with the federal scheme." Although federal law does not require E-Verify's use, a state's decision to make E-Verify mandatory "is entirely consistent with the federal law."
Turning to implied preemption (Justice Thomas did not join these sections of the opinion because he rejects implied preemption in its entirety), a four-member plurality concluded: "Arizona's procedures simply implement the sanctions that Congress expressly allowed Arizona to pursue," and they are entirely consistent with federal law. Arizona adopts the federal definition of an unauthorized alien. State investigators must rely on a federal determination of a particular employee's status and may not attempt to make an independent determination. Arizona law, like federal law, punishes only knowing or intentional violations. And the sanctions of license suspension and revocation, although severe, are typical attributes of a licensing scheme. Arizona's law is thus not impliedly preempted.
Chief Justice Roberts delivered the opinion of the Court, in which Justices Scalia, Kennedy, and Alito joined in whole, and in which Justice Thomas joined in part. Justice Breyer filed a dissenting opinion in which Justice Ginsburg joined. Justice Sotomayor filed a dissenting opinion. Justice Kagan took no part in the consideration or decision of the case.