The U.S. Court of Appeals for the 5th Circuit vacated a preliminary injunction blocking enforcement of Texas Senate Bill 4 on Friday, clearing the way for state law enforcement to arrest migrants suspected of illegal entry.

In a 10-7 en banc decision authored by Judge Jerry E. Smith, the court ruled that the plaintiffs, immigrant advocacy groups Las Americas Immigrant Advocacy Center and American Gateways, along with El Paso County, lack Article III standing to challenge the law. The majority held that the organizations' claims of resource diversion and mission impairment do not constitute cognizable injuries, as they cannot manufacture standing by voluntarily incurring expenditures that oppose the statute. "That should be the end of this matter: These Plaintiffs voluntarily incurred costs to advocate for clients," the opinion stated.

The court did not address the merits of whether SB 4 is preempted by federal immigration law. The case returns to the Western District of Texas for further proceedings.

SB 4, enacted in December 2023, makes illegal entry into Texas from a foreign country outside a port of entry a state misdemeanor punishable by up to six months in jail. It authorizes any peace officer to arrest suspects without a warrant if there is probable cause and permits state magistrate judges to order convicted individuals to return to Mexico instead of further prosecution. The law also criminalizes illegal reentry after a prior deportation or conviction under the statute.

Texas passed SB 4 amid record migrant encounters at the southern border, which state officials described as an invasion. Encounters have since declined significantly. The measure faced immediate legal challenges from the Biden administration and civil rights groups, who argued it usurps exclusive federal authority over immigration.

The law has ping-ponged through courts since 2024. A federal district judge blocked it hours before its scheduled effective date in March 2024. The U.S. Supreme Court allowed temporary enforcement, but a 5th Circuit panel reinstated the block. The full court heard en banc arguments earlier this year before Friday's ruling.

Texas Attorney General Ken Paxton hailed the decision as "yet another major win for Texas." "Texas’s right to arrest illegals, protect our citizens, and enforce immigration law is fundamental. This is a major victory for public safety and law and order," Paxton said. Governor Greg Abbott's office echoed the sentiment: "Texas will not back down from its constitutional right to self-defense."

Advocates for immigrants expressed dismay. "This ruling is a procedural decision, not a ruling on the merits," said Cody Wofsy of the ACLU’s Immigrants’ Rights Project. The ACLU vowed to continue the fight, noting that prior courts have found similar laws unconstitutional. Las Americas called the ruling alarming, warning it would foster fear among migrant families.

It remains unclear whether SB 4 will take effect immediately, as the Trump administration has withdrawn the Department of Justice from the lawsuit. Texas officials have not announced specific enforcement plans, but the state has invested heavily in Operation Lone Star, its border security initiative.