EL PASO — Attorney Jorge Dominguez arrived early Wednesday at his small office at Las Americas Immigrant Advocacy Center to listen in as attorneys sparred over Senate Bill 4, the Texas law that lets state officials arrest migrants who cross illegally into the country.

Wearing a sweatshirt and jeans, the lawyer paid close attention as a judge asked the Texas solicitor general what would happen if officers bring someone to a port of entry but federal authorities refuse to take them. Dominguez was stunned by the answer: He wasn’t sure.

“The Texas counsel is saying ‘I don’t know’ to a lot of important questions,” Dominguez said.

Even before the latest legal developments, Texas’s implementation of S.B. 4 was causing confusion and uncertainty. But anxiety and fear over the controversial law is reaching a new level as local leaders, police departments, civil rights advocates and migrants await the outcome of a court battle that turned dizzying this week.

“Some people say we can be deported. Others say we’ll be arrested if we leave this shelter,” said Maria Alejandra Seijas García, a 23-year-old from Venezuela staying at a refuge for migrants in El Paso. “It just seems unfair to me. Shouldn’t we be protected if we are in an asylum process?”

The Supreme Court briefly allowed the law to take effect Tuesday, but the U.S. Court of Appeals for the 5th Circuit blocked enforcement hours later and heard the oral arguments Wednesday without issuing a ruling. The law makes illegal entry into the country a state crime, allowing state and local law enforcement to arrest people who are suspected of the crime and return them to ports of entry. The law was originally scheduled to go into effect March 5.

It was the most aggressive border proposal pushed last year by Gov. Greg Abbott, a third-term Republican who is a fierce critic of President Biden and his immigration policies. Republicans consider the issue one of Biden’s biggest vulnerabilities as he faces his GOP predecessor, Donald Trump, in the November presidential election.

But how the Texas law might be enforced remains a point of contention, including among law enforcement agencies who would be tasked with making arrests. In recent days, police departments across the state have put out statements expressing concern about taking on immigration enforcement responsibilities. Some city leaders have been explicit in discouraging officers from making arrests under the new law.

El Paso Mayor Oscar Leeser said Wednesday his office has been monitoring the legal developments but doesn’t plan to change how city police work regardless of the outcome.

“We’re not going to racially profile anyone,” Leeser said. “We will not implement immigration laws.”

Javier Salazar — the sheriff of Bexar County, home to San Antonio — said Monday he was drafting a new policy to help his officers understand the law if it goes into effect. The department would also require an “extensive” report if an officer makes an arrest under the law, he said during a news conference, making clear he personally disagreed with it.

“We need our deputies to understand that, ‘Hey, look, we may not be allowed to tell you you can’t enforce a law,’” Salazar said. “What we are saying, though, is, ‘If you choose to do it, you’re assuming some liability for yourself, you’re putting this agency in a whole lot of liability, and we want to make sure that you know exactly what you’re doing and what you’re getting into before you start going into all of this effort for a misdemeanor.’”

The police department in Fort Worth — Texas’s fifth-most-populous city — signaled Monday it was uninterested in taking on the responsibility of deporting people in the country illegally.

“Although we will always follow the law, the primary responsibility for immigration enforcement and border protection should be left to our federal and state partners,” the department said in a post on X.

Other departments have taken more of a wait-and-see approach as the court battle unfolds.

The confusion especially affects people like Dominguez, a young attorney who represents immigrants who have been detained in federal facilities. The organization he works for is a plaintiff in the lawsuit regarding S.B. 4.

The other day, Dominguez said, a client who had just obtained a work authorization permit asked him bluntly whether such a document would protect him as someone in an immigration process from being suspected as being illegally present in El Paso.

“There are so many people in limbo status and the law is so vague that we don’t know how it will be enforced if the 5th Circuit decides to allow S.B. 4’s implementation,” he said. “But a work permit is likely not enough.”

For Texas Republicans, the case is yet another rallying cry in a long-running tradition of battling Democratic presidential administrations.

Abbott struck a defiant tone on the topic as he addressed a conservative think tank in Austin on Wednesday. Acknowledging the legal fight has been “like a tennis match,” Abbott insisted Texas was still finding ways to arrest people who cross the border illegally.

“Know this: What they have stayed is the Texas enforcement of S.B. 4, but even without S.B. 4, Texas has the legal authority to arrest people coming across the razor wire barriers on our border,” Abbott said, “and we continue to use our arrest authority and arrest people coming across the border illegally.”

Abbott added that lawmakers wrote the law “to be consistent with the dissent that was written in that Arizona case by Justice Scalia.” In his dissent, Scalia wrote that a state has the “sovereign power to protect its borders more rigorously if it wishes, absent any valid federal prohibition.”

The border remains the foremost issue in Texas politics, especially among Republicans, who are currently locked in a civil war. On Tuesday, the state House speaker, Dade Phelan, found himself defending his support for S.B. 4 after his primary challenger, David Covey, attacked him for not voting for it. (The speaker rarely casts votes on legislation.)

A number of high-profile Democrats who are immigrants themselves have spoken out against the law, expressing fear that they and others will be racially profiled if S.B. 4 is enforced.

“Under SB 4, it’s conceivable that an anti-immigrant officer could arrest someone for little more than them ‘looking like an immigrant,’” Harris County Judge Lina Hidalgo, who leads the county that is home to Houston, said in a statement. “That possibility alone makes our community nervous, and with good reason.”

More than anything, Texas officials appear to just want clarity from the courts.

El Paso County’s highest-ranking elected official, Judge Ricardo Samaniego, was getting home Tuesday evening when he started fielding calls from the county legal department about the latest tumult involving S.B. 4. He was getting real-time analysis while reading text messages from community members struggling to understand the latest news.

“I feel like I’m on a roller coaster and I just want to know if the roller coaster is going up or going down, but I haven’t left the ride,” Samaniego said after a luncheon with city business leaders, where he addressed the disruption the law would bring. “I can’t trust anything. Today they say that. Tomorrow, what are they going to say?”

For some migrants, the law has already had an impact, even while it remains on pause. Lendys Fernandez, 32, of Venezuela, is seven months pregnant with her first child. She had a consultation with a local doctor scheduled for Wednesday, but she said that the driver backed out, out of fear over the law.

“They weren’t sure what could happen because technically we are undocumented,” Fernandez said, pulling out a stack of documents from federal immigration authorities after she surrendered and was released 19 days ago. She is authorized to travel the country, but she doesn’t know if that will matter at all to a Texas law enforcement officer.

On Wednesday, she rested in a cot alongside Seijas García at the El Paso shelter. They tried to decipher TikTok posts on how the law might be enforced. All of Seijas García’s clothing, toiletries and personal items were stuffed into a bulging duffel bag. She said she was afraid Texas would deport her after what had been a long and torturous journey to request asylum in the United States.

“Do you know how it feels after walking for months, going hungry for days, alone and with the sun beating on us, to make it and just be returned?” she said. “It doesn’t seem right.”