The American Civil Liberties Union (ACLU) and the ACLU of Arizona filed a federal lawsuit on behalf of the Florence Immigrant and Refugee Rights Project, challenging Section 5 of Proposition 314.

This provision, previously postponed, would unconstitutionally usurp federal immigration control power by making the entry or stay of some immigrants in Arizona a state crime.

Courts across the country have repeatedly reaffirmed that immigration control is the exclusive power of the federal government, not the states.

Section 5 had been on hold due to litigation against similar laws in other states, but is now about to go into effect. The groups are asking the court to immediately block the provision, alleging a violation of the Supremacy Clause of the United States Constitution, which clearly states that immigration is a federal responsibility.

“Section 5 of Proposition 314 authorizes state and local law enforcement to commit blatantly unconstitutional acts, including racial profiling, unlawful arrests, and unlawful detention,” stated Tara DeGeorge, legal director of the ACLU of Arizona.

"It will destabilize Arizona's courts, overload an already overcrowded state prison system, and lead to numerous due process violations. Arizona communities should not pay the consequences of this unconstitutional experiment," he added.

The groups are asking for a temporary restraining order and preliminary injunction to prevent the harm Section 5 would cause to immigrant, Latino and communities of color across the state.

“Section 5 of Proposition 314 creates a completely separate and parallel detention and deportation system,” stated Roxana Avila-Cimpeanu, deputy director of the Florence Immigrant and Refugee Rights Project.

“If it goes into effect, countless members of our communities, including vulnerable youth and people with mental health issues, could end up incarcerated across Arizona on state immigration charges, intentionally isolated from specialized legal assistance, and potentially deported without ever receiving a fair trial.”

"The regulation of immigration to the United States is an exclusively federal power that cannot be usurped by Arizona or any other state. The Supreme Court reaffirmed this fundamental principle in response to an unconstitutional Arizona law 14 years ago," said Kate Huddleston, senior staff attorney at the ACLU's Immigrant Rights Project.

“Section 5 of Proposition 314 is equally illegal and inhumane, which is why we are filing a lawsuit to block it,” he added.

Proposition 314 was passed by the Arizona Legislature in 2024 and ratified by voters that same year, but Section 5 remained dormant while a similar anti-immigrant law in Texas, Senate Bill 4, was blocked in the courts.

The Fifth Circuit Court of Appeals vacated a lower court's injunction against Senate Bill 4 solely on procedural grounds on May 15. Section 5 of Proposition 314 goes into effect after a comparable state law has been in effect for 60 days.

Without judicial intervention, state and local law enforcement agencies can begin enforcing Section 5 starting July 14.