The Justice Department filed suit today in Phoenix against the state of Arizona on grounds that the state’s new immigration law illegally intrudes on federal prerogatives. The U.S. is seeking a preliminary injunction to stop the legislation from taking effect this month as scheduled, reports the Washington Post. The suit invokes as its main argument the legal doctrine of “preemption,” which is based on the Constitution’s supremacy clause and says that federal law trumps state statutes. Justice Department officials believe that enforcing immigration laws is a federal responsibility.
The filing also contained a civil rights component, arguing that the Arizona law would lead to police harassment of U.S. citizens and foreigners. President Obama has warned that the law could violate citizens’ civil rights, and Attorney General Eric Holder has expressed concern that it could drive a wedge between police and immigrant communities. The case will dramatically escalate the legal and political battle over the Arizona law, which gives police the power to question anyone if they have a “reasonable suspicion” that the person is an illegal immigrant. The measure has drawn condemnation from civil rights groups and has prompted at least five other lawsuits. Arizona officials have defended the law.