- Arizona legislative leaders will join the defense of the state’s new border enforcement law in federal court.
- A federal hearing on July twenty-fourth, twenty twenty-six will consider an emergency injunction against Proposition 314.
- Critics argue the law violates the Supremacy Clause by creating a parallel state-level immigration enforcement system.
Attorney General Kris Mayes and Arizona’s Republican legislative leaders will defend the state’s new border-enforcement law at a federal hearing after a judge allowed the lawmakers to intervene in the case. The hearing is scheduled for July 24, 2026, before U.S. District Judge Michael Liburdi.
The case challenges Section 5 of Proposition 314, which became enforceable statewide on July 14, 2026. That provision makes illegal entry from a foreign nation a state crime, permits state and local police to arrest people accused of unlawful crossings, and allows state judges to issue “Orders to Return to Foreign Nation.”
The American Civil Liberties Union and the Florence Immigrant and Refugee Rights Project filed the lawsuit on July 10. They are seeking an emergency injunction that would block enforcement while the case proceeds.
The judge has not yet ruled on that request. The measure remains under challenge in federal court.
On July 16, Liburdi granted permission to House Speaker Stephen Montenegro and Senate President Warren Petersen to join the defense. The Republican lawmakers argued that Mayes might not adequately protect their interests because she opposed the measure politically before voters approved it.
“They cannot be assured — for multiple reasons — that Attorney General Mayes, the main defendant in this matter, will adequately represent their interest,” attorneys for Petersen and Montenegro wrote in court filings. Beau Roysden represents the legislative leaders.
Mayes has assigned lawyers to defend the law as Arizona’s chief legal officer. Her office has also said it is prepared to defend the measure despite her earlier opposition. The lawmakers cited her past refusal to defend laws such as the 15-week abortion ban as evidence that her defense might not be vigorous.
The lawsuit targets state control over immigration enforcement
The lawsuit, Florence Immigrant and Refugee Rights Project v. Mayes, argues that the law conflicts with federal immigration authority. The challengers say the Supremacy Clause prevents Arizona from creating its own system for criminalizing unlawful entry and ordering people removed from the country.
The legal dispute reaches beyond arrests. The law gives state judges authority to issue removal orders, creating what the advocacy groups describe as a parallel state process alongside federal immigration proceedings.
Tara DeGeorge, legal director at the ACLU of Arizona, said the provision could encourage actions by local and state officers that the Constitution does not permit.
“Section 5 of Proposition 314 is a permission slip for local and state law enforcement to engage in blatantly unconstitutional acts like racial profiling, unlawful arrests, and illegal detentions.”
Roxana Avila-Cimpeanu, deputy director at the Florence Immigrant and Refugee Rights Project, said the state process could interfere with existing federal cases.
“Proposition 314 would create a completely new, parallel system that would frustrate the work [advocates] are doing in the federal immigration processes already.”
The challengers also warn that Latino and immigrant communities could face increased surveillance and profiling from local police who lack federal immigration training.
The lawmakers say they need their own lawyers
Petersen and Montenegro received permission to intervene because they claimed a direct interest in defending a law enacted through the Republican-led legislature and approved by voters. Their separate defense now proceeds alongside the representation provided by Mayes’ office.
The measure, also known as the “Secure the Border Act,” passed at the November 2024 election by a margin of more than 3-2. Republican lawmakers placed it on the ballot after Democratic Gov. Katie Hobbs vetoed a similar proposal, SB 1231, in March 2024.
The lawmakers’ intervention does not resolve whether the law is constitutional. It gives them a formal role in arguing that Arizona may enforce the challenged provisions.
Mayes opposed the measure before its enactment. She nevertheless remains the named state defendant and has committed her office to the formal defense now before Liburdi.
That split has shaped the case. Republican leaders questioned whether the attorney general would defend the law with enough force, while Mayes’ office has proceeded with its legal obligations as the state’s chief lawyer.
Section 5 followed the Texas timetable
Arizona lawmakers drafted the illegal-entry provision to take effect only after a similar Texas law survived legal challenges or remained enforceable for 60 days. Texas SB 4 supplied that trigger.
The provision became enforceable July 14, 2026, following the Fifth Circuit’s May 15 action in the Texas litigation. The timing put Arizona’s state-level entry restrictions into operation while the federal challenge was already pending.
The law now authorizes state and local police to arrest people accused of entering Arizona unlawfully from a foreign nation. It also gives state judges authority to issue Orders to Return to Foreign Nation.
Those powers differ from the federal immigration process at issue in the lawsuit. The challengers argue that Arizona cannot replace or supplement the federal government’s control over admission, removal and immigration enforcement.
The court must first decide whether to pause enforcement. A ruling on the emergency injunction could determine whether the provisions operate during the broader constitutional case.
Other sections require immigration-status checks for benefits
The entry provision has drawn the lawsuit, but the broader law contains additional requirements. Other sections require state and local agencies to check immigration status through federal databases before providing public benefits such as Medicaid, known in Arizona as AHCCCS, or food stamps.
Those verification rules are separate from the arrest and court-order provisions challenged in Section 5. The lawsuit’s immediate request focuses on stopping the state deportation scheme while the case moves forward.
The practical consequences could reach people who entered Arizona outside official ports of entry. They may face state-level prosecution and court-ordered removal under the challenged provisions, subject to the federal court’s decisions.
The advocacy groups say local enforcement could also affect people who have existing federal immigration cases. Avila-Cimpeanu described the state system as an additional process that could complicate work already handled through federal immigration proceedings.
The constitutional question remains unresolved. The Supremacy Clause argument will be tested at the July 24 hearing, where the parties are expected to address whether the law should be blocked before the court decides the full case.
This article provides general information and is not legal advice. Consult a qualified immigration attorney about your specific case.
