AUSTIN, Texas — Texas civil rights groups filed a new lawsuit seeking to block parts of Senate Bill 4, passed in 2023, as the law is set to take full effect May 15 following a recent federal appeals court ruling.

Nearly three years after Texas lawmakers passed Senate Bill 4, legal battles continue over whether key provisions can be enforced. The American Civil Liberties Union of Texas and the Texas Civil Rights Project filed the new lawsuit today after the 5th U.S. Circuit Court of Appeals lifted a lower court ruling late last month that had been keeping the law from taking effect.

Senate Bill 4 makes illegally crossing the U.S.-Mexico border a state-level crime and allows Texas police to arrest people for it. Following the appeals court ruling, the law is scheduled to begin full enforcement May 15.

“Immigration is up to the federal government, not the states. That’s exactly what the district court in our original case said,” said Caro Rivera Nelson, an attorney for ACLU of Texas.

Rivera Nelson said the new lawsuit targets the law’s re-entry provision and other related sections. “It doesn’t specifically challenge the entry provision. So as it stands, if we are successful in our lawsuit, the re-entry provision would be halted before the May 15th enforcement date. We, for the same reasons that we think the re-entry provision is unlawful, we think the entry provision is also unlawful.” she said.

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The re-entry crime would apply to individuals who illegally re-enter the country without federal authorization.

Rivera Nelson said the new filing is an attempt to revive the challenge with new plaintiffs and again seek to stop the law from being enforced. “What we’re doing today is bringing the case back with different plaintiffs and really trying to continue to have an injunction against what we believe to be a completely unlawful law,” she said.

Republican state Rep. Brian Harrison of Waxahachie said the 5th Circuit ruling clears the way for enforcement after years of injunctions. “Now it’s up to the Texas government. The Texas government needs to get on to get about this and go ahead and enforce this law. It’s a positive development,” Harrison said. He also criticized opponents of the measure, saying, “groups, organizations that support open borders are going to continue doing everything they can to get back to what they consider the glory days of the Biden border invasion.”

It is also Harrison’s stance that it’s up to the state of Texas to secure the border. “So this is very important for the long term future of the state of Texas and America,” he said.”

The role that Texas police and law enforcement plays in immigration enforcement in the state has been the subject of several protests already in 2026.

The lawsuit also challenges provisions that give power to magistrates to issue deportation orders, make it a crime to fail to comply with a magistrate’s removal order, and require magistrates to continue a prosecution even when a person has a pending injunction case under federal law.

Texas Attorney General Ken Paxton’s office was contacted for comment on the lawsuit, and a response is pending.