Like virtually all politicians who win re-election, U.S. Sen. Pat Toomey returned to Capitol Hill eager to get back to last session’s unfinished business. Unlike other elected officials, though, Toomey's top priority just happened to dovetail with one of President Donald Trump's early agenda items.

As a result, as the junior senator prepares to reintroduce a bill that would withhold federal dollars from so-called sanctuary cities, which limit their cooperation with immigration authorities, his push has been immeasurably buttressed by the president's signing of an executive order to strip federal grant money from such municipalities. Either action could land Philadelphia, which has more than 1.5 million of Toomey’s constituents, among the cities caught in Toomey’s crosshairs.

The senator’s bill is supported by President Trump, who said that one of his post-election priorities would be cutting federal funding to sanctuary cities that have caused “so many needless deaths” due to their immigration policies.

Toomey’s latest version of the bill targeted Community Development Block Grants from the U.S. Department of Housing and Urban Development, which funded $38.8 million of affordable housing, economic development and public improvements in Philadelphia last year. Alabama Sen. Jeff Sessions, Trump’s nominee for U.S. attorney general, wants to punish these cities by withholding law enforcement funding. In fiscal year 2016, Philadelphia was allocated $1.68 million in justice assistance grants from the U.S. Department of Justice that would be cut under Sessions’ plan.

With so much on the line, should citizens and leaders in sanctuary cities be concerned?

Responses from immigration experts boiled down to: “Meh, not really. … Maybe a little. … Everyone settle down.”

First, they said, it’s important to realize that this isn’t a new issue.

Members of Congress have been pushing similar bills for years, according to Doris Meissner, a senior fellow at the nonprofit Migration Policy Institute. She previously served as acting commissioner for the U.S. Immigration and Naturalization Service during the Reagan administration and as INS commissioner during the Clinton administration.

“None of them have been enacted, and part of the reason is because it’s been quite difficult to come up with a way of doing what some in Congress want to do and what the administration wants to do,” she explained. “It’s one thing to say, ‘We’re going to withdraw funds.’ It’s another to figure out how to accomplish it.”

Another challenge is defining just what a sanctuary city is. Sundrop Carter, executive director of the Pennsylvania Immigration and Citizenship Coalition, said the misnomer is creating a lot of confusion about what U.S. Immigration and Customs Enforcement can do.

“There are no cities where people are protected from deportation. ICE can walk into any building in any city in the U.S. and deport them,” Carter said. “This is not about policy. This is about rhetoric. Who is the real American? Is it the white American, the Christian American, or do we include black and brown people and Muslims?”

Philadelphia Mayor Jim Kenney said his preferred term is “Fourth Amendment city,” since local authorities will not cooperate with immigration officials unless they have a signed warrant. The Fourth Amendment of the U.S. Constitution says “people” cannot be held against their will without a warrant. Since it does not specify “residents” or “citizens,” some interpret that to mean it covers any individual in the U.S., legally or not.

Kenney and leaders in other sanctuary cities say their interpretation keeps law enforcement officers free to concentrate on public safety. They contend that turning local officers into immigration enforcers can damage their relationships with immigrant communities, discouraging some from reporting crimes against them.

“That could create a community where people can prey on people who can’t report crimes – it makes the whole community much more volatile as a whole,” said Avideh Moussavian, a policy attorney with the National Immigration Law Center. He said withholding police funds to punish sanctuary cities, as Sessions had proposed, seemed “completely counterintuitive. People in law enforcement know that to do their work, they need to encourage the comfort and safety of their community members, to engage them and encourage them to report information, whether they are crime victims or witnesses,” he said.

Another challenge would be identifying which municipalities deserve to be disciplined. Philadelphia is wearing its heart – in the form of its sanctuary city policy – on its sleeve. But what about Pittsburgh, which has not raised a sanctuary city flag, but has similar policies?

Timothy McNulty, a spokesman for Mayor Bill Peduto, said media reports that the Pittsburgh City Council was considering a formal sanctuary city declaration were false.

Asked to explain the city’s practices regarding immigration, McNulty said, “Pittsburgh’s policy is to work with all federal agencies, including ICE, to detain criminals being sought for arrest. At the same time, we protect the constitutional rights of our citizens from being questioned without reason about their immigration status. Pittsburgh Police are not immigration officers.”

Pittsburgh seems to be following the same policies as Philadelphia. But without any official declaration, would it be eligible for potential sanctions? Organizations on both sides of the immigration debate estimate there are about 400 jurisdictions with written policies that mandate cooperation with immigration authorities. But what about the rest of them? Would federal officials need to consider every municipality individually to determine which ones should be punished? How much would that cost?

Meissner, of the Migration Policy Institute, said it’s safe to assume that even if a bill denying federal funding to sanctuary cities were to pass, those affected would immediately file lawsuits to block the action. And they’d have a strong case, she said, especially if the funds being withheld had nothing to do with immigration.

“There are court decisions that say the federal government can’t engage in coercive actions where funding is concerned,” she said.

This is not to say that there have never been efforts on a federal level to control state decisions by threatening to withdraw money. In 1984, Congress passed the National Minimum Drinking Age Act, which allowed it to withhold 5 percent of federal highway funding from states that did not establish a minimum drinking age of 21.

The law was challenged by South Dakota. The U.S. Supreme Court upheld the law by a 7-2 margin and established a five-point rule for considering the constitutionality of funding cuts. Chief Justice William Rehnquist wrote in the majority opinion that since the cut was a small percentage of the total federal funding, “The relatively small financial inducement offered by Congress here … is not so coercive as to pass the point at which pressure turns into compulsion.”

While the president and his supporters have been vocal about punishing jurisdictions they feel violate the law, longtime policy watchers, like Moussavian of the National Immigration Law Center, encourage keeping calm while also being observant.

“This has been a prominent issue for the president, but that doesn’t change the limits on the federal government’s ability to tell cities how to do their work,” she said. “Just because someone says something loudly doesn’t make it

more true.” ■