Editor's note: This story has been updated throughout to reflect Friday's oral arguments at the the U.S. 5th Circuit Court of Appeals.

The immediate future of Texas' immigration enforcement law hinges on whether a three-judge panel in New Orleans was swayed Friday by the state’s attorneys that the legislation is essential to public safety and should not have been partially blocked by a federal judge days before it was scheduled to go into effect.

Attorneys on both sides of the issue used most of their allotted 40 minutes on Friday before the U.S. 5th Circuit Court of Appeals debating two major provisions of Senate Bill 4: whether local governments can be required to honor all ICE detainers, and whether local governments can be required to assist immigration officers on other matters.

As passed, SB 4 prevents police chiefs, sheriffs and other local leaders from preventing peace officers from questioning the immigration status of people they detain or arrest. It also seeks to punish local government department heads and elected officials that limit cooperation with federal immigration officials, including those who don’t cooperate with "detainers" — requests by agents to turn over immigrants subject to possible deportation. Punishment could come in the form of jail time and penalties that exceed $25,000.

The Texas Tribune thanks its sponsors. Become one.

Last month, U.S. District Judge Orlando Garcia halted the part of the bill that required jail officials to honor all detainers. He also blocked other sections that prohibit local entities from pursuing “a pattern or practice that 'materially limits' the enforcement of immigration laws” and another that prohibits “assisting or cooperating” with federal immigration officers as reasonable or necessary.

The Texas Attorney General’s office is asking the 5th Circuit court to lift those blocks while the case winds through the appeals process. 

During oral arguments Friday, Judge Stephen Higginson told Texas Solicitor General Scott Keller repeatedly that everything he knows to be true about ICE detainers reflect they are not mandatory.

“All of the federal authority, the [Immigration and Naturalization Act] the [request] forms themselves, the way the circuits have interpreted these ICE detainers, everything has been premised on the understanding that federal law makes it voluntary,” he said, according to an audio recording of the proceedings.

But Texas Solicitor General Scott Keller said the provision of SB4 that requires jails to honor ICE detainers should be allowed to stand because although they are deemed voluntary by the federal government, state governments have a right to compel local entities to act.

“There is a difference between the federal government saying ‘This is voluntary because we cannot compel it’ and a state saying ‘We are directing our localities as part of our sovereignty - because localities are creatures of the state - to honor these.’”

The Texas Tribune thanks its sponsors. Become one.

Later, the plaintiffs attorneys argued that other provisions of the legislation are too broad and that the court should deny the state’s request to lift the injunction so there was more time to consider those issues through court filings and more debate.

Lee Gelernt, an attorney with the American Civil Liberties Union, cited specifically the section of SB4 that would penalize elected or appointed leaders for adopting policies that prevent assisting or cooperating with federal immigration agents.

He said that it’s unclear if even in extraordinary times, like last months devastation after Hurricane Harvey hit Houston, if discretion would be allowed.

“These are split-second decisions. Take the call that [local officials] are going to get in Houston,” Gelernt said. “It says ‘Go help us [enforce immigration], even at the shelters.’ Does [a police chief] run in to try and get a temporary restraining order or does he say I am not going to do that and risk enormous penalties?

“The problem runs through the entire statute, you have people on the ground who are not going to be sure what they can limit and what they can prohibit.”

In motions filed before Friday's arguments, lawyers for the state argued that SB 4 is essential to keeping the public safe.

“SB 4 is wholly valid, and the State has every right to prohibit its own localities from having sanctuary-city policies,” Scott Keller, the Texas solicitor general, argues in the state’s motion to lift the injunction. “Moreover, the Order even threatens existing and legitimate local voluntary cooperation with the federal government’s enforcement of immigration law.”

But opponents of the law, which include the cities of El Cenizo, Austin, Houston, San Antonio and El Paso, say that claim is flawed because SB 4 was never enacted in the first place.

The Texas Tribune thanks its sponsors. Become one.

“The legal landscape today is the same as the landscape on August 29, 2017, the day before the District Court issued its order,” plaintiffs' attorneys, which include the Mexican American Legal Defense and Educational Fund, the Texas Civil Rights Project and the American Civil Liberties Union, argue in their response. “Neither the State’s misreading of the terms of the injunction nor its sky-is-falling rhetoric can manufacture harms.”

Another issue in the legal debate is whether a local entity choosing to detain a person based solely on suspected immigration status – and not because another crime was allegedly committed – violates the Fourth Amendment, which protects against unreasonable searches and seizure by the government. Garcia cited the amendment in calling for a halt to SB 4's detainer provision, but Texas’ attorneys will argue that the Fourth Amendment doesn’t extend to immigrants living in the country illegally.

“Neither this court nor the Supreme Court has held that the Fourth Amendment extends to a native and citizen of another nation who entered and remained in the United States illegally,” Keller argued in his motion. “So it is doubtful that the Fourth Amendment even applies to many aliens subject to ICE detainers under SB 4.”

Even if it did apply, the state added, Garcia was wrong to limit state or local compliance with detainer requests because those entities are aiding a federal agency, which is legally able to ask for such assistance.

“It makes no difference whether state officials carry out the first 48 hours of that detention at the express request of the federal government,” Keller stated. “That is especially so since a federal ICE-detainer request to state officials is backed by a federal immigration warrant.”

But the opponents’ attorneys argue that other district courts that also fall under the 5th Circuit’s jurisdiction have found that detention based solely on suspected immigration status violates the Fourth Amendment.

“The State cites no decision holding that local officials may constitutionally detain an individual on probable cause of removability – much less that local officials must cede to third parties their duty to make a probable cause determination,” they argued.

A timeline for a ruling on the state's request to allow the full law to go into effect isn’t certain. But the court has already scheduled a separate hearing for November for the appellate court to hear arguments on the injunction itself and whether the case should proceed on its merits.

Read related Tribune coverage:

  • Texans who benefit from the Deferred Action for Childhood Arrivals program learned that the popular program will be phased out. And they have a second worry: the fate of the state's new immigration enforcement law. [Full story]

  • Days before Hurricane Harvey hit Texas, a federal district judge halted a controversial state-based immigration enforcement law just before it was scheduled to go into effect. [Full story]

  • While a federal judge allowed parts of Texas' "sanctuary" law to move forward, a Latino advocacy group said those provisions wouldn't create drastic changes in the way local law enforcement operates. [Full story]

Never miss a moment in Texas politics with our daily newsletter.