In states across the country, Republican lawmakers are aiming to combat sanctuary cities and counties, and in some cases banding together to develop new ways to prod local jurisdictions into helping enforce federal immigration law.

While these efforts are not unique—18 states introduced legislation to limit sanctuary policies in the 2016 state legislative session—they are taking a stronger force at a time when the Trump administration has begun reviewing how to punish sanctuary cities by withholding federal grant funding.

At the same time, states, cities, and counties that provide protection to immigrants living illegally in their communities have refused to back down.

According to the National Conference of State Legislatures, at least 29 states and Washington, D.C., are considering legislation in 2017 regarding sanctuary jurisdictions or noncompliance with immigration detainers.

Of these states, 25 states would prohibit sanctuary policies and 8 states and Washington, D.C., would support them. Five states have legislation on both sides of the issue.

“The role of state and local law enforcement in federal immigration policy has returned to the forefront of public debate,” Ann Morse of the National Conference of State Legislatures wrote in her synopsis of state-level legislative action.

Here are three strategies states are proposing to challenge sanctuary cities.

1. Criminal Prosecution

The Republican-controlled Texas Senate last month passed legislation that subjects leaders of sanctuary cities and counties to criminal prosecution if they refuse to honor requests, known as detainers, from federal immigration officers to hand over illegal immigrants in custody for possible deportation.

“If elected officials want to flaunt state law there will penalty,” said state Rep. Charlie Geren, a Republican who is finalizing a similar bill in the Texas House that may include a criminal liability component.

Colorado’s state Rep. Dave Williams, a Republican, has been rebuffed by Democrats in advancing legislation that would allow people to file civil suits and criminal complaints against “lawless politicians.”

Democrats alleged it would be unconstitutional to subject local politicians to a lawsuit or criminal prosecution.

Despite his bill’s quick demise in a state where Democrats control the House and governorship, Williams, a freshman of Mexican descent, has touted his Colorado Politician Accountability Act on national television, and like-minded lawmakers in other states have cited his efforts as inspiring them.

“My bill may be effectively dead, but this effort will continue to make elected officials think twice before implementing sanctuary policies that endanger the public,” Williams told The Daily Signal.

Heeding this call for action, Ohio state Rep. Candice Keller, a freshman Republican, is drafting a bill—her first ever—to ban sanctuary cities, and she is consulting with Williams in considering whether to include a civil and criminal liability element.

“Last month, I called Dave and I said, ‘Do you care if I take off on this sanctuary city bill?’” Keller told The Daily Signal. “He’s been supportive and he periodically checks in on me.”

2. Imposing Fines and Blocking Funds

In Florida, Republican lawmakers emboldened by the results of November’s election have introduced bills that would impose an array of penalties on cities and counties that have sanctuary immigration policies.

The Rule of Law Adherence Act, authored by state Sen. Aaron Bean, contains a provision that would would impose a fine of up to $5,000 a day on any government entity that is found to have a sanctuary policy. It would also withhold state grant funding for five years from any government entity that violates the act.

Bean acknowledges there is no formal definition of a sanctuary policy and that a law enforcement agency would have to demonstrate a “practice” of declining detainer requests to qualify for punishment.

“If a jurisdiction were to decline one or two detainers, that would not qualify,” Bean said. “We don’t really want to fine anyone. We really just want to say, ‘Work with federal immigration authorities.’”

The law does not go as far as others in that it does not leave politicians open to criminal prosecution—only civil liability.

It would allow government agencies to be sued should a person who is in the country illegally injure or kill someone as a result of an entity having a prohibited sanctuary policy.

“If any one agency or entity engages in sanctuary policies, it puts our entire state at risk, and so we are going to act, take away your immunity, and hold you accountable,” Bean told The Daily Signal.

Bean admits he faces an “uphill battle” to turn his legislation into law, even in a state that is fully controlled by Republicans. A similar bill to outlaw sanctuary policies failed last year even with a GOP-led legislature.

But the threat of action has already prompted Miami-Dade County to eliminate its sanctuary protections.

Acting on a order from Mayor Carlos Gimenez, a Republican, the Miami-Dade County Board of County Commissioners last month adopted a resolution to fully cooperate with requests from federal Immigration and Customs Enforcement (ICE).

Gimenez acted one day after President Donald Trump issued his executive order threatening to crack down on sanctuary cities. The mayor said he didn’t want to put the county at risk of losing $355 million a year that it receives in federal funding.

Miami-Dade’s previous policy, codified in a 2013 resolution, limited what kind of ICE detainers it would honor to include only suspects convicted of serious, violent crimes.

Over recent years, local governments across the U.S. began to resist fully complying with detainers, which are requests by ICE to hold an arrested individual beyond their normally scheduled release so federal immigration officers can take custody of them.

U.S. appeals courts have ruled that cooperating with detainer requests is voluntary—not required—for local jurisdictions.

The courts have said ICE detainers violate the Fourth and Fifth Amendments. A Miami-Dade judge ruled Friday that holding inmates for ICE is unconstitutional.

Jean Monestime, a Miami-Dade County commissioner who authored the 2013 resolution limiting cooperation with ICE detainers, told The Daily Signal he would continue to fight efforts that mandate sanctuary jurisdictions to change their policies.

“This is an issue of fairness, it’s an issue of due process, and it’s an issue of protecting our community to allow undocumented folks to not be afraid to report crimes to law enforcement,” said Monestime, who opposed the mayor’s order restoring full cooperation with ICE . “I don’t think this position helps make our community safer.”

3. ‘A Warning Shot’

Some Republican lawmakers opposing sanctuary cities are taking a more cautious approach.

In Iowa, where Republicans have total state control for the first time since the 1990s, bills introduced in the House and Senate would dictate that all cities and counties must help enforce federal immigration law.

But state Rep. Steven Holt said his legislation would not impose fines or withhold funding from jurisdictions that don’t comply with the law’s provisions.

“My legislation is an important statement that rule of law matters and protection of Americans should come first,” Holt said. “But it has no teeth in it in terms of financial penalties. We thought that would be a bridge too far. This is a warning shot.”

No city or county in Iowa formally recognizes itself as a sanctuary, although the City Council in Iowa City adopted a policy in January that denies allocation of local resources to federal immigration enforcement.

“We all know the vast majority of people without documentation are here for a better life, but it just takes one bad case of a violent criminal being released to harm Americans,” Holt said.

Eleanor Dilkes, the city attorney in Iowa City, told The Daily Signal that the council will not change its policy, even if Holt’s bill becomes law.

“Iowa City’s reaffirmation that city resources will continue to be used for public safety and not the enforcement of federal immigration law would not be affected if this bill were to become law,” she wrote in an email.

Questions Remain

In Tennessee, a state with full Republican control, there is already a law on the books prohibiting local governments or law enforcement officials from making policies that prevent compliance with federal immigration requests.

That law, like the ones proposed in Iowa, does not contain financial penalties for noncompliance.

There aren’t any official sanctuary cities in Tennessee.

Yet state Sen. Mark Green, a Republican, says it’s important to be proactive, and he boasts about legislation he recently introduced that withholds state funding from jurisdictions that resist immigration enforcement.

“There was a sanctuary city bill that passed a few years ago that made these policies illegal, but it had no teeth,” Green said. “We are putting teeth with the bill.”

But Green is running into roadblocks. The office of Tennessee Gov. Bill Haslam, a Republican, recently notified Green that the state constitution prohibits the withholding of education funding to communities. So Green is amending his legislation to say the state cannot block education funds.

“We want to make sure the legislation is foolproof against legal challenges,” Green said.

Even so, legal experts say sanctuary states and localities likely will challenge state and federal laws requiring compliance in enforcing federal immigration law.

“It’s one thing for a state to ask local law enforcement officers to enforce state law,” said Pratheepan Gulasekaram, a Santa Clara University immigration law professor, in an interview with The Daily Signal. “These debates are interesting, odd, and different, because they are proposed state laws that create penalties for nonparticipation in federal law enforcement. This will make these laws subject to due process litigation.”

Other law experts say states have wide authority that even protects tougher proposed policies such as those in Texas and Colorado that threaten criminal prosecution against sanctuary cities.

“It would be legal for states to impose criminal liability on their own officials for refusing to cooperate with federal immigration authorities, as the Texas bill would do,” said Michael Dimino, a constitutional law professor at Widener University.

“That does not mean that the bills will be free from constitutional challenge,” Dimino wrote in an email to The Daily Signal. “On the contrary, I think it is clear that suits will be brought alleging that they violate the immigrants’ rights. But if state law requires state officials to cooperate with federal immigration officials, I cannot see any decent argument that those state officials would have for refusing to comply with the law.”