This week, the United States sent a clear message to the state of Arizona: Let the Dreamers drive.

In a friend-of-the-court brief filed in the U.S. Court of Appeals for the Ninth Circuit, the United States urged the Court to affirm its decision from this summer invalidating Arizona’s ban on granting driver’s licenses to young immigrants who came to the county as children as unconstitutional.

To recap how we got here: Arizona’s driver’s license ban reflects state officials’ rejection of the Obama administration’s decision two years ago to authorize Dreamers to live in the country and grant them work permits under the Deferred Action for Childhood Arrivals (DACA) program. In August 2012 – the first day the federal government began accepting DACA applications – Arizona Governor Jan Brewer issued an executive order announcing that the state would continue to view Dreamers as illegal immigrants and deny them driver’s licenses on this basis.

The ACLU and its allies filed suit on behalf of the Arizona Dream Act Coalition and individual Dreamers challenging Arizona’s policy as unconstitutional. In May 2013, district court judge found that the policy likely violated the Equal Protection Clause because it singled out Dreamers for discrimination. But rather than abandon its policy, Arizona doubled-down on discrimination by denying even more immigrants licenses, including the survivors of domestic violence and victims of serious crimes.

The effects of this ban have been devastating. In a state with average highs of over 100 degrees in the summer and limited public transit, Arizonans have to drive to live their daily lives. Indeed, more than 87 percent of Arizonans commute to work by car. And yet as a result of Arizona’s policy, about 21,000 Dreamers have been banned from the roads.

This past July, the Ninth Circuit finally held that Arizona’s policy violated the Equal Protection Clause. And yet even now, Arizona has refused to abide by the ruling, instead asking the court to reconsider its decision, while making Arizona taxpayers foot the bill for their lawyers.

The United States’ brief filed this week, urged the court to affirm its decision. It’s reasoning was simple: Arizona may have decided for itself that Dreamers are “illegal” immigrants and thus ineligible to drive. But under federal law, Dreamers have been authorized to live and work in the country through the federal DACA program. Because Arizona has no authority to decide who is and isn’t allowed to live in the country, its policy must be struck down.

Fortunately, unlike Arizona, most of the country has gotten with the program. Forty-eight states have decided to let the Dreamers drive; only two – Arizona and Nebraska, where the ACLU has also filed suit – have opted to exclude them. The United States’ brief is an important reminder to the minority of states that have not welcomed Dreamers that they have no place discriminating against people in the face of federal action.

As the Obama administration looks toward new executive action on immigration before the end of the year, we hope that all states reject Arizona’s path of discrimination and welcome the immigrants who already are a part their communities.

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