What Can a State Do About Immigration? Ten Answers From Arizona v. United States

When a governor signs an immigration bill, you can predict the next two weeks. One group declares victory. Another group declares the end of the republic. And a team of lawyers, who will be doing the actual work for the next several years, quietly opens a file called "preemption." If you want to understand red-state immigration law, and I think every conservative who follows state politics should, the word you have to master is that one. It is the legal doctrine that decides who wins when a state law and a federal law collide, and it is where almost every state immigration law lives or dies.

The best teacher on the subject is a single decision: Arizona v. United States, decided on June 25, 2012. It was about a state law, SB 1070, and it drew lines that every legislature since has had to respect. Below are ten questions and answers drawn from it. I am a booster of states doing their part, and I am telling you honestly that the Court's opinion cuts both ways. Knowing exactly how is how you avoid cheering for a bill that will be struck down.

The case in brief

1. What was SB 1070?

SB 1070 was an Arizona law signed in April 2010 by Governor Jan Brewer, called the Support Our Law Enforcement and Safe Neighborhoods Act. It was written to apply what its supporters called "attrition through enforcement," making life harder for people in the state unlawfully. The federal government, then under President Obama, sued to block it, arguing that the Constitution leaves immigration to Washington.

Four provisions reached the Supreme Court. Section 3 made it a state crime to fail to complete or carry a federal alien registration document. Section 5(C) made it a state crime for an unauthorized alien to seek or hold a job. Section 6 let state officers arrest without a warrant anyone they had probable cause to believe had committed a public offense that made the person removable. And Section 2(B) required officers who stopped, detained or arrested a person to make a reasonable attempt to determine immigration status if they had reasonable suspicion that the person was unlawfully present.

2. What did the Court decide?

The Court, in an opinion by Justice Kennedy, held that Sections 3, 5(C) and 6 were preempted by federal law and could not take effect. It held that Section 2(B), the status check, could go forward, at least in a pre-enforcement challenge. Justice Kagan did not take part. So the headline is a split decision: three provisions down, one standing. Each side claimed a win, and both were partly right.

The doctrine behind it

3. What is preemption, and where does it come from?

The Supremacy Clause in Article VI makes federal law "the supreme Law of the Land." When a valid federal law and a state law conflict, the state law yields. Courts talk about three kinds.

• Express preemption. Congress says in the statute that state law on the subject is displaced.
• Field preemption. Congress has regulated so thoroughly in an area that it left no room for states to add anything.
• Conflict preemption. A state law either makes it impossible to obey both laws, or stands as an obstacle to the purposes of Congress.

The root of the immigration cases is old. In Chy Lung v. Freeman (1875) the Court struck down a California law that burdened the arrival of immigrants, because the national government controls foreign commerce and relations. In Hines v. Davidowitz (1941) the Court held that Pennsylvania could not add its own alien registration requirements on top of the federal registration law, because Congress had created a single, comprehensive national system. Justice Kennedy leaned on Hines in 2012, and it is the case to know.

4. Why did Section 3, the registration crime, fall?

Because of Hines. Federal law already requires noncitizens to register and to carry registration papers, and it sets penalties. Arizona's Section 3 added a state penalty for the same conduct. The Court said Congress had occupied the field of alien registration, and a state could not add its own crime, even one that mirrored federal law. A state that punishes what federal law punishes, in its own courts, on its own terms, is not helping the federal system. It is running a parallel one.

5. Why did Section 5(C), the work crime, fall?

This one is the most interesting, and it is where conservatives should pay attention. In 1986, when Congress created the system of employer sanctions, it chose to penalize employers who hire unauthorized workers, but not the workers who take the jobs. Congress had considered penalizing workers and decided against it. Arizona's Section 5(C) did what Congress had chosen not to do, so the Court held that it stood as an obstacle to the balance Congress struck. The point is subtle: a state can be preempted not only by what Congress wrote but by a deliberate choice Congress made not to write something.

6. Why did Section 6, the warrantless arrest power, fall?

Because it gave state officers an arrest authority that federal law does not give even to federal immigration officers in the same circumstances, and because Congress had set out specific, limited ways for state officers to take part in enforcement. Under the 1996 law, state and local agencies can enter written agreements with the federal government, known as 287(g) agreements, to perform immigration enforcement functions under federal supervision and training. Removal decisions are also entrusted to federal officials, who weigh discretion, foreign relations and humanitarian concerns. A state officer making arrests for removability on his own would insert the state into decisions Congress reserved for federal officers. I describe the 287(g) route in A County Sheriff's Playbook for Joining ICE Under 287.

What survived

7. What was left of Section 2(B), and what is the catch?

The status check survived, and that is the biggest piece of the decision for red states. The Court said it was too early to say that checking status during a lawful stop would conflict with federal law, because Congress has long encouraged cooperation. The federal code says that state and local officers may communicate with federal immigration officials about the status of individuals and may cooperate in identification, apprehension, detention and removal. All eight justices who heard the case agreed on that result.

But there were three catches the Court was careful to flag. First, it read the provision to apply only where the stop was lawful to begin with. Second, it said the check should not extend a stop longer than it would otherwise take, meaning a person could not be held beyond the time needed for the original purpose solely to verify immigration status. Third, it left the door open to later challenges if the law was applied in a way that violated federal law or the Constitution. So a state that copies Section 2(B) has a law that can be defended, but it has to be carried out carefully, with training and clear rules for officers.

The dissents and the sovereignty argument

8. What did Justice Scalia say, and why does it matter?

Justice Scalia wrote separately, concurring in part and dissenting in part, and Justices Thomas and Alito also dissented in part. Scalia would have upheld all four provisions. His argument rested on state sovereignty. He contended that the States did not surrender their traditional power to decide who may enter and remain within their territory, except to the extent federal law validly limits it, and that Arizona had a sovereign interest in protecting itself from the effects of unlawful immigration. In his view, a state law that is consistent with federal law should not be struck down just because the federal executive prefers not to enforce it.

That is a serious position held by serious conservative jurists, and it is the one boosters often cite. But recognize what it is: a dissent. The majority view is that immigration is a field where the national government holds the lead, and states act within the room Congress leaves. If you are writing a bill for a legislature, write for the majority, not the dissent. For the principle behind both, see the discussion of federalism and the Tenth Amendment in The Tenth Amendment Rule That Protects Red States Also Protects Sanctuary Cities.

Where states have room

9. What did earlier and later cases say about employers?

Two other cases show where the room is. In De Canas v. Bica (1976), the Court upheld a California law that penalized employers who knowingly hired workers not authorized to work, finding that regulating the employment of people in the state was a traditional exercise of the state's police power and that Congress had not displaced it. Then, in 1986, Congress passed its own employer sanctions law, with an express preemption clause that bars states from imposing civil or criminal sanctions on employers who hire unauthorized workers, "other than through licensing and similar laws." That exception was the opening Arizona used.

In Chamber of Commerce v. Whiting (2011), one year before Arizona v. United States, the Court upheld an Arizona law that allowed the state to suspend or revoke the business licenses of employers who knowingly hire unauthorized workers and required employers to use E-Verify. That decision gave states a real tool against the demand side of unlawful immigration. I describe the system itself in E-Verify Explained, the Free Federal Check Most Employers Skip. The contrast between Whiting and Section 5(C) is the cleanest summary of the whole field: states may regulate the employer through licensing, but may not criminalize the unauthorized worker in a way Congress declined to.

A later case adds a footnote. In Kansas v. Garcia (2020), the Court allowed states to prosecute people under ordinary state identity-theft and fraud laws for using false Social Security numbers on employment forms, rejecting the argument that federal law preempts every state law that touches the I-9 paperwork. Generally applicable state criminal law, in other words, still applies.

10. So what can a state actually do?

Here is the working list, drawn from the cases above. It is not legal advice, and each item should be checked against current law before a legislature votes.

1. Cooperate with federal authorities. Federal law lets state and local officers share information and assist, and 287(g) agreements allow formal partnerships.
2. Check status during lawful stops, with care. Section 2(B)-style laws survived a facial challenge, subject to the limits on prolonging stops.
3. Regulate employers through licensing, and require E-Verify. Whiting is the model.
4. Apply general criminal law. Identity theft, forgery and fraud laws apply to everyone, as Kansas v. Garcia shows.
5. Decide its own benefits and services. Federal welfare law of 1996 restricts public benefits for people unlawfully present, and states may provide them only by enacting a law that says so.
6. Direct its own cities and counties. A state can bind its subdivisions about whether they cooperate with federal enforcement, which I discuss in The Tenth Amendment Defense of Sanctuary Cities, and Where It Runs Out.
7. Use its attorney general. State attorneys general can bring suits, file briefs and challenge federal policy, a role discussed on the Republican attorneys general pages of this site.

And here is what a state cannot do, or at least cannot do safely:

• Create its own immigration crimes that duplicate or add to the federal scheme, as in Sections 3 and 5(C).
• Give its officers independent authority to arrest for removability, as in Section 6.
• Run its own deportations or decide who may stay in the country.
• Deny public school to children because of their parents' status, because of Plyler v. Doe (1982), a case that conservatives have long criticized but that remains the law, and that states must obey until the Court says otherwise.

Honest caution is warranted on the newer fights. States have continued to pass laws testing the boundaries, and some are in litigation. I am not going to describe the status of any of them, because it changes. Check the state legislature's website and the federal court docket before you quote a result.

The lesson for citizens

If you take one thing from Arizona v. United States, take this: constitutional law rewards patience and precision. A legislature that writes a bill to match the Court's guidance can get something durable. A legislature that writes a bill for applause can get a headline, an injunction and a legal bill paid by taxpayers. The difference is often the difference between a bill drafted by lawyers who read the case and a bill drafted by someone who watched a news segment.

You also have a role. State legislators respond to voters, and the national conversation about immigration is mostly about Washington, but a great deal of the practical action is in your state capital. Ask your legislators what their bill does under the Arizona framework and who reviewed it. Look at how Republican officials in your state have used their offices on the Republicans page.

The bottom line

• Arizona v. United States (June 25, 2012) struck down three SB 1070 provisions, the registration crime, the work crime and the warrantless arrest power, and let the status-check provision stand.
• States get the most room when they cooperate with federal authorities, license and regulate employers, and apply ordinary criminal law. They get the least when they build a parallel immigration system.
• Justice Scalia would have upheld all four provisions on state sovereignty grounds, but that was a dissent. Draft bills for the majority opinion.
• Before you cheer for a new state immigration bill, ask whether it copies Whiting or Section 5(C), because one survived and the other did not.
• Check your state legislature's website for the text and the federal court docket for the status. Laws in this area change fast.