Immigration plans by Donald Trump and Ron DeSantis face obstacles

As they vie for the 2024 GOP presidential nomination, Donald Trump and Ron DeSantis have tried casting themselves as the candidate most harshly against illegal immigration. The two Republicans have made similar promises, but are likely to face the same obstacles if either is elected and tries to implement them.

Trump and DeSantis have vowed to finish building a border wall, detain every person who illegally crosses into the U.S. and prevent children born in the U.S. to parents here illegally from automatically becoming U.S. citizens.

Many of these goals would need congressional funding, an immigration system overhaul or even a new amendment to the Constitution. 

Here’s a sampling of both candidates’ promises and the facts standing in their way.

Trump and DeSantis say they will end "catch and release" — a term Republicans often use to describe immigration authorities stopping immigrants at the border and releasing them so they can await their court hearings outside of federal custody. 

But both Democratic and Republican administrations have followed this practice for decades, because there’s limited detention space and court rulings have capped how long someone can be detained. 

Immigration experts say that realistically, this practice cannot be ended, especially by only executive action. It would require Congress enacting a new law and massive investments in personnel, detention capacity and infrastructure to detain every immigrant who crosses the border without authorization. 

Congress has appropriated funds for about 34,000 detention beds in fiscal year 2023, but there is a backlog of 2 million pending cases in immigration court (which can take years to resolve), according to data from Syracuse University’s Transactional Records Access Clearinghouse. 

In January 2017, Trump signed an executive order to end "catch and release." But a few months later, his own attorney general testified to the Senate that the practice continued because of the long case backlog and an immigration judges shortage. 

Ending "catch and release" would require detaining everyone — including families — who arrive at the border. But this pledge ignores that courts have said that children (whether they arrive alone or with a parent or guardian) cannot be detained indefinitely by immigration authorities.

DeSantis and Trump have both said they will end birthright citizenship for children born in the United States to parents who are here illegally. Trump also promised this in 2016, but failed to achieve it, earning a Promise Broken on PolitiFact’s promise tracker. 

Birthright citizenship stems from the Constitution's 14th Amendment, which says that "all persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the state wherein they reside."

An 1898 Supreme Court decision also ruled that people born on United States soil, with a few clear exceptions, qualify for citizenship under the 14th Amendment. A 1952 law also supports this concept. 

If elected, the most DeSantis or Trump could unilaterally do is sign an executive order with the expectation that a lawsuit from opponents would follow, said Kermit Roosevelt, a University of Pennsylvania law professor. Then, birthright citizenship’s fate could be in the courts’ hands.

U.S. Border Patrol agent Jesus Vasavilbaso looks into Mexico at a breach in the 30-foot-high border wall where a gate was never installed due to a halt in construction, Sept. 8, 2022, in Sasabe, Arizona. (AP)

DeSantis and Trump have vowed to finish a border wall along the nearly 2,000 mile U.S.-Mexico border, but large parts of the U.S. southern border are on privately owned or federally protected land. So barriers can’t be placed there, unless the federal government buys the land or seizes it via eminent domain.

Achieving this promise would also require cooperation from Congress, which would need to appropriate funding for this purpose.

Both candidates say a wall would decrease illegal immigration, but experts have questioned barriers’ effectiveness.

Instead of lowering the number of people crossing, border barriers have mainly prompted people to try crossing at different parts of the border, said David Bier, a Cato Institute immigration studies director. And the prospect of an impenetrable wall with no gaps anywhere "is just ludicrous," he said. 

"You're always going to have someone who comes along and puts a gap in the wall. And once that happens, then people can move through it," Bier said. "And so, it's really selling a false picture of what's going to happen if they do complete this project."

DeSantis’ immigration plan says he "will deport visa overstays." The plan does not explain how he will achieve that promise and his campaign didn’t elaborate to PolitiFact. 

Every year, the United States grants thousands of visas for foreign students, tourists and workers. Some foreigners overstay their visa briefly; others overstay for years. 

There is no precise number of immigrants in the U.S. illegally who have overstayed their visas, but there are some estimates. In 2022, about 850,000 foreigners, or 4% of the total number of people who were supposed to leave as their visa expired in fiscal year 2022, stayed, according to a report from the Department of Homeland Security.

Robert Warren, a senior visiting fellow at the Center for Migration Studies, said data suggests that about 40% of all immigrants living in the U.S. illegally overstayed their visas. That puts the total number of visa overstayers at around 4.6 million.  

Deporting mass numbers of people is also challenging for the federal government.

There are three main reasons a mass deportation program — which would include people who overstayed their visas — would not work, Warren said.

• The government does not know where these immigrants live;

• The cost and manpower needed to remove 10 million people would be staggering; and

• The Constitution prevents U.S. government agents from randomly knocking on doors to ask about immigration status. 

The money and staffing needed to track down everyone who overstayed a visa would also take resources away from tracking down criminals, which would be a waste, Bier said. 

"In other words," Warren said, "a mass deportation program would likely be illegal and a blunder on a colossal scale."

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