Christian Science Monitor via Getty Images The Texas State Capitol is seen through the trees on Feb. 22 in Austin, Texas.

A parade of Texas law enforcement officials once again registered their opposition Wednesday to a Republican-backed effort to crack down on “sanctuary” jurisdictions that limit their cooperation with immigration authorities.

But conservative lawmakers seem poised to ignore them.

SB 4, which would fine local officials that refuse to comply with “detainer” requests to hold undocumented immigrants on behalf of the federal government, has already passed the full state Senate. The House State Affairs hearing Wednesday marked the bill’s first step on its way through the legislature’s lower house. Most of the state’s Republican lawmakers view it as a commonsensical effort to enforce the immigration laws already on the books.

But several police officials from the state’s largest cities have cautioned that the law would make their jobs more difficult by alienating immigrants and making law enforcement vulnerable to liability for increased racial profiling that they say will likely accompany the bill’s implementation ― criticisms widely shared by legal experts and immigrant families.

Austin Police Chief Brian Manley said pressing his officers to help enforce immigration law would distract them from their core responsibilities. “It’s going to pull my officers away from their more important duties of combating crime,” Manley said.

Bexar County Sheriff Javier Salazar said passing the bill would alienate immigrants, as the police would begin taking on a greater role in federal immigration enforcement.

“It’s imperative that we maintain trust with the communities we serve,” Salazar told the committee. “We risk driving this segment of the population into the shadows. … I have seen examples where victims of domestic violence are told by their abuser, ‘Go ahead and call the cops. You know where you’re going.’”

Ed Gonzalez, the sheriff of Harris County, which includes Houston, said he suspected the bill would make the state less safe by making unauthorized immigrants fearful of calling the police if they see a crime.

“I think that inherently when someone witnesses something traumatic, there’s already going to be fear,” Gonzalez said, “let alone when they fear they themselves will be deported.”

One woman described suffering precisely that experience. She told the committee that it took three years for her to find the courage to call the police to report an abusive partner ― even after he held a gun toward her, threatening to shoot her and then himself if she left him.

“I was worried that if I called the police, I would be asked about my immigration status and then deported,” she said. “You will be empowering the abusers and giving them another tool to carry out their abuse [if you pass SB 4].”

Legal experts also cautioned that letting police play a greater role in federal immigration enforcement would open the state up to lawsuits.

“Let’s be clear,” Celina Moreno, an attorney with the Mexican-American Legal Defense and Education Fund, said. “Racial profiling is a foreseeable consequence of SB 4.”

Kali Cohn, an attorney with the American Civil Liberties Union, added that jurisdictions that honor all requests from Immigration and Customs Enforcement to hold undocumented immigrants can be sued for violating the Fourth Amendment, which guarantees protection from unlawful searches and detention.

“An ICE detainer asks a local law enforcement agency to hold someone for 48 hours,” Cohn said. “But when those additional 48 hours begin, local law enforcement still need probable cause to make that detention. The problem is they can’t point to probable cause because ICE detainers are not supported by probable cause.”

Several Texans who either have undocumented family members or were undocumented themselves said the bill would threaten their safety. “My dad isn’t an alien,” one young girl said through tears. “He’s a human being and he should be treated like one.”

The vast majority of those who testified asked the legislature to abandon the bill. Of 638 who registered, only 11 urged lawmakers to pass the bill, according to Texas state Rep. Rafael Anchia (D-Dallas). The hearing continued well into the evening.

Opposition from law enforcement notwithstanding, Texas lawmakers are likely to pass the measure against sanctuary cities.

Republicans have tried to ban sanctuary cities for years, despite the fact that the vast majority of local officials honor virtually all federal requests to hold undocumented immigrants in local jails on behalf of ICE. But conservative efforts to pass such legislation have failed in the past because Democrats had enough votes to block floor debate in the state Senate.

Last year, Republicans loosened the century-long tradition of requiring the votes of two-thirds of the state Senate to make it easier to pass a conservative agenda, in a state where they control all three branches of government.

Despite conservative emphasis on ridding the state of cities with liberal immigration policies, currently the only jurisdiction to limit its cooperation with ICE is Travis County, where Austin is. In January, Travis County Sheriff Sally Hernandez adopted a policy of declining to hold immigrants for ICE if they qualify for release or bond, unless they are convicted or charged with one of a short list of crimes including murder, sexual assault and human trafficking.

Texas Gov. Greg Abbott (R) responded by stripping the county of $1.5 million in state grants and threatening to find a way to remove Hernandez from office.