Will Texas succeed in enforcing its own immigration law?

GREG ABBOTT, the governor of Texas, watched his dream of a state-run immigration policy become reality this week. On March 19th America’s Supreme Court ruled that Texas could—at least temporarily—enforce Senate Bill 4 (SB4), a law that makes it a state crime for migrants to cross Texas’s border with Mexico between legal ports of entry (see map). The bill gives local police the authority to arrest people they suspect of coming to America illegally and empowers state judges to order deportations. This was the first time that a state had assumed these powers, which had been reserved for the federal government.

But Mr Abbott’s triumph lasted less than nine hours. The Supreme Court’s emergency ruling was a stopgap that lobbed the question of SB4’s legality down to the Fifth Circuit Court of Appeals, the region’s federal appellate court. That night three judges in New Orleans decided to put the law on hold while they deliberate on its merits in the coming weeks. Immigration advocates who worried that SB4 would put a target on Latinos’ backs were relieved; Mr Abbott said he felt as if he was watching a tennis rally.

Map: The Economist

Mr Abbott thinks Joe Biden’s policy on immigration is too lax. Acting on that belief, he has picked a legal fight over which level of government has the right to control border policy. In January the Biden administration sued Texas over SB4, arguing that it violates the supremacy clause of the constitution, which makes the federal government the chief arbiter of immigration policy. Texas reckons that it is being “invaded” by migrants. On that basis it claims a right to defend itself under the state-war clause of America’s constitution—which forbids states from waging war without the consent of Congress unless they are “actually invaded” or in “imminent danger” of it. Ken Paxton, Texas’s attorney-general, has said that he hopes to provoke the Supreme Court into revisiting its decision in 2012 in the case of Arizona v United States, which set the precedent that states cannot enforce their own immigration regimes. Legal experts expect the question of SB4’s constitutionality to bounce back to the nine justices in the coming months.

To persuade the court Texas’s lawyers will have to prove two things. First, that the migrants pose enough of a threat to justify declaring war against them. And, second, that Texas can override federal law in order to defend itself. That will be hard. Appellate courts in California, New York and Pennsylvania have interpreted the constitution’s reference to invasion to mean armed hostility by political enemies or foreign armed forces. It is difficult to imagine how asylum-seekers fit that description. The Supreme Court has also held that if the federal government responds to such an invasion, states must “give way” to federal policy. That would suggest that, although Texas loathes the Biden administration’s border policy, the very  existence of that policy is an argument against the constitutionality of the state’s plan.

SB4’s boldness makes it legally precarious. It is a far bigger flex of state power than the governor’s previous moves to bus migrants to Democrat-controlled cities or install razor wire along the Rio Grande to prevent migrants from crossing the river. In the unlikely event that he ever succeeds in enforcing his own immigration scheme, Mr Abbott will have to contend with problems that go beyond domestic politics. Mexico’s foreign ministry said on March 19th that the country will not accept migrants deported by Texas. It pledged to negotiate only with America’s federal government.