Debate over the extent states can enforce immigration law is ramping up nationally, as several states are pushing for similar measures to a contentious Texas law that allows police to arrest — and state judges to deport — migrants.

Arizona, Iowa, Idaho, and Oklahoma are among the states passing or considering measures similar to Texas’s Senate Bill 4, which is being weighed by a Fifth Circuit court panel after oral arguments in April. Texas’s legislation has been the subject of legal debate for months, as it was challenged by the Biden administration on the grounds that the law violates the Constitution’s Supremacy Clause. Also central to the legal debate is a Supreme Court case from 2012, Arizona v. United States, which held immigration matters to be in the federal government’s purview. 

As legislative battles are unfolding in several states, immigration advocates across the country have been rallying against Texas’s law and expressing concerns that it will set a “disastrous precedent” for other states if not blocked in court. 

Texas’s Senate Bill 4 is “being mimicked in state legislatures across the country that put immigrant communities and families at risk,” a senior legal director at the American Immigration Council, Kate Melloy Goettel, said in a statement. “All these bills could result in significant civil rights abuses, leading to widespread arrests and deportations by state actors without key federal protections.”

Yet the Republican states enacting the legislation argue that it’s an attempt to protect themselves where the Biden administration has failed. 

“Since President Biden took office in 2021, more than 10 million people have poured over the southern border,” Governor Stitt of Oklahoma said when he signed legislation at the end of April making illegal entry a state crime. “Countless individuals from across the globe, including thousands of Chinese nationals as well as people affiliated with terror organizations, have illegally crossed the U.S.-Mexico border.”

Oklahoma’s legislation states that it “is a compelling public interest of this state to protect its citizens” and its borders, and adds that a “crisis” exists in the state as law enforcement “comes into daily and increasingly frequent contact” with illegal immigrants. 

Similar legislation is being considered in Idaho, and Arizona’s legislature is considering whether to approve a ballot measure that — if enacted by voters — would make it a state crime for foreign nationals to enter the state except through a lawful port of entry. 

The Justice Department sued Iowa this month for its recently passed legislation mimicking Texas’s law. The Justice Department’s lawsuit against Iowa reads similar to its filing against Texas, arguing that the federal government is seeking to “preserve its exclusive authority under federal law to regulate the entry and removal of noncitizens.”

Because Iowa’s legislation, like Texas’s Senate Bill 4, requires state judges to deport noncitizens, the Justice Department argues, the legislation intrudes on the federal government’s authority, “frustrates” immigration operations, and “interferes” with foreign nations and America’s relations with them. 

“Iowa cannot create its own immigration system,” the filing notes. Citing Arizona, the Biden administration contends it has “broad, undoubted power over the subject of immigration and the status of noncitizens,” and that state laws must “give way” to federal authority when the two conflict. 

Iowa’s governor, Kim Reynolds, promptly fired back that it was her duty to protect Iowa in the federal government’s absence. 

“Since President Biden refuses to enforce our nation’s immigration laws – threatening the safety of our citizens – Iowa will step in,” she said.