Sometimes the legal issue behind a highly visible political controversy is more technical than the public debate would make it seem. That is the case with Arizona v. United States, the high-profile dispute over Arizona’s recent sweeping immigration statute, which the Justices will consider at their private Conference today; the Court could announce as early as Monday whether it will review the case.

The political issue in Arizona’s appeal is how much leeway states have to regulate immigration in light of the comprehensive system of federal immigration law. The legal issue is one that has repeatedly drawn the Supreme Court’s attention in an another immigration case from Arizona, and many other contexts, in the last few years – preemption.

The concept of preemption is fairly simple to state, but much more difficult to apply. Federal law takes precedence over state law. This principle is stated in Article VI, paragraph 2 of the Constitution, commonly referred to as the Supremacy Clause, which provides that the “Constitution, and the Laws of the United States which shall be made in Pursuance thereof . . . shall be the supreme Law of the Land . . . any Thing in the Constitution or Laws of any State to the Contrary notwithstanding .”

The challenge of defining preemption law – i.e., when a particular law is invalid because it conflicts with or is otherwise displaced by federal law – is dramatically demonstrated by the Supreme Court’s preoccupation with the subject. Since early 2008, the Court has decided at least ten preemption cases, and it is already slated to consider at least three more this Term. And although preemption can arise in a variety of contexts, in recent years the balance between state and federal regulation of products – from prescription drugs to medical devices to car seatbelts – has been the most frequently recurring question.

The critical question is when a federal law preempts a state law. It is not the case that there is preemption simply because a federal law and a state law relate to the same subject. The clearest case is when Congress specifically says that it intends to preempt all state laws in a field; this is called express preemption.

The more difficult disputes involve what is called “implied preemption”: when Congress has not made its intention entirely clear. Courts may find implied preemption in two different scenarios. The first, which is sometimes called “conflict preemption,” occurs when there is (wait for it . . .) a conflict between federal and state laws that makes it difficult or impossible to comply with both. The second kind of implied preemption occurs when Congress passes a law that is comprehensive and leaves no room for state regulation; this is sometimes called “field preemption” because Congress has occupied the field.

The Arizona immigration law raises a number of these issues. The Constitution , in Article I, section 8, paragraph 4, gives Congress the power “[t]o establish an uniform Rule of Naturalization.” The federal government has long asserted that the power to regulate immigration rests almost entirely with Congress and the executive branch and that federal immigration laws are intended to be comprehensive. At the same time, federal officials encourage state and local police to cooperate with federal immigration law enforcement efforts.

Cooperation did not seem to be Arizona’s main motivation in passing the law. When Governor Jan Brewer signed the legislation, known as S.B. 1070, in April 2010, she described it as “another tool for our state to use as we work to solve a crisis we did not create and the federal government has refused to fix.” Alabama, which recently passed a more restrictive immigration law, has defended its action in lower federal court proceedings on the basis of a need to stem the tide of unlawful aliens. In seeking Supreme Court review, however, Arizona now argues that its law is an effort to cooperate with federal enforcement.

Four provisions in S.B. 1070 are in dispute. First, the law instructs Arizona law enforcement officials to try to determine an individual’s immigration status any time someone is arrested, as well as during a police stop or arrest if they have reason to believe that the individual may be an unlawful alien. Second, the law makes it a violation of Arizona law for someone to fail to register as an alien under federal law. A third section makes it illegal for unlawful aliens to work or to try to obtain work. The fourth provision gives Arizona police the power to make warrantless arrests of anyone whom they have probable cause to believe has engaged in activity that would make them deportable under federal law.

The U.S. Justice Department sued to block the Arizona law. A federal judge issued a preliminary injunction against the four provisions, finding that federal law likely preempted Arizona’s efforts. In April 2011, a three-judge panel of the U.S. Court of Appeals for the Ninth Circuit upheld the preliminary injunction, agreeing with the federal government that the district judge had not abused her discretion in issuing the injunction. One member of the panel , however, would have held that two of the four provisions were not preempted. Arizona then filed a petition for certiorari in which it cited an urgent need to be able to enforce state law. The Justice Department has opposed Supreme Court review.

Underlying the preemption issue that the Court has been asked to review is a debate over the respective roles of the federal government and the states in immigration issues. The federal government’s assertion is that immigration policy is entirely a federal issue, in part because of the Constitution’s provision delegating power over naturalization to Congress and in part because immigration issues are an important part of foreign policy, which is the exclusive prerogative of the president and Congress.

Although Arizona argues that S.B. 1070 represents an effort to cooperate with the federal government, the federal government counters that “cooperation” is a narrow concept that requires state and local law enforcement officials to operate within the framework of federal law. The state role is to provide information to help support federal enforcement. What Arizona has done instead, the Ninth Circuit found, is to create its own, separate immigration policy – which Ninth Circuit Judge John Noonan described as a policy of “attrition” that was intended to actively reduce the numbers of unlawful aliens in the state.

Arizona argues that the system of federal enforcement is “broken” and that “it is widely recognized that the federal immigration laws are not adequately enforced.” This failure of federal efforts, the state argues, should give the states more leeway to adopt immigration laws that will make a difference in the flow of unlawful aliens across borders into the United States.

The Supreme Court’s fascination with the problems of preemption in recent years does not shed a lot of light on what the Court might do with the Arizona case. Although the Justices have undoubtedly hoped to clarify the legal standards for preemption, the results have been very mixed, with the Court finding preemption in some cases but not in others and with no real clarity emerging from the decisions.

Among the Court’s ten preemption rulings, though, is one that may be more relevant than others. Last May, by a vote of five to three (with Justice Kagan recused), the Court held that another Arizona immigration law was not preempted by federal law. In Chamber of Commerce v. Whiting, the Court concluded that an Arizona statute which allows the state to revoke the business licenses of companies that hire and employ unlawful aliens did not conflict with federal law. Writing for the majority, Chief Justice John Roberts reasoned that the particular provision of federal law in question intended to leave room for state enforcement.

Just how the Supreme Court will resolve the new Arizona dispute may become apparent soon. The Court could opt to decline review at this point and to instead wait for another opportunity to resolve the preemption conflict between federal law and state enforcement of immigration. Or the Court may feel that the moment is ripe to step into this important dispute between the states and the federal government.

Recommended Citation: Stephen Wermiel, SCOTUS for law students: Preemption and the Arizona immigration law, SCOTUSblog (Dec. 9, 2011, 1:37 PM), https://www.scotusblog.com/2011/12/scotus-for-law-students-preemption-and-the-arizona-immigration-law/