This Date in Obama's Administrative AmnestyOn this date four years ago, the Obama Administration filed an amicus brief on behalf of the U.S.

Chamber of Commerce asking the U.S. Supreme Court to strike down a 2007 Arizona law that punishes employers who knowingly hire illegal aliens. “The Legal Arizona Workers Act,” signed by then Arizona

Governor Janet Napolitano, requires all Arizona employers to use the federal E-Verify system, and allows Arizona to suspend and/or revoke the business licenses of employers who knowingly hire illegal aliens.

The Chamber of Commerce filed a lawsuit in 2007 — in what became known as the Chamber of Commerce v. Whiting seeking to strike down the Arizona law by arguing that federal law preempts both provisions. However, at the time the Chamber sought review by the U.S. Supreme Court, both lower courts, including the Ninth Circuit Court of Appeals, had already upheld it. In particular, even the Ninth Circuit viewed it as an exercise of a state’s traditional power to regulate businesses.

Ultimately, in May 2011, the U.S. Supreme Court agreed that the law was not preempted, and rejected the Chamber and Obama Administration arguments in a 5-3 decision. Importantly, the Court held that while federal law prohibits the Secretary of Homeland Security from making E-Verify mandatory for the states, nothing prohibits the states from doing so themselves. The Court also upheld the Arizona law’s licensing provisions.

The Supreme Court’s decision in Whiting was monumental in paving the way for more states to enact mandatory E-Verify legislation. In fact, more than a dozen states have E-Verify laws on the books.