S.B. 4 is an unusual measure by any standard. The statute allows Texas to more or less enforce its own immigration laws. Under S.B. 4, illegal entry into the United States is a state-level crime, empowering state law enforcement agencies to make arrests for potential violations of it. The law also allows Texas to theoretically carry out its own deportations for anyone found guilty of the offense. State officials argued it was necessary because the Biden administration wasn’t doing enough to “secure the border.”
The Constitution gives that power to the federal government, however, not to the states. Courts have long held that states can’t carry out their own immigration priorities. In 2012, the Supreme Court struck down an Arizona law that allowed state and local police to enforce federal immigration laws and created a series of state-level offenses that would allow it to prosecute undocumented immigration. Justice Anthony Kennedy, writing for the 5–3 majority, held that the law intruded upon federal discretion over immigration enforcement.
“The national government has significant power to regulate immigration,” he wrote for the court. “With power comes responsibility, and the sound exercise of national power over immigration depends on the nation’s meeting its responsibility to base its laws on a political will informed by searching, thoughtful, rational civic discourse. Arizona may have understandable frustrations with the problems caused by illegal immigration while that process continues, but the state may not pursue policies that undermine federal law.”