(Bloomberg) -- Calls by some top Democratic presidential contenders to decriminalize border crossings have divided the party and risk turning the issue of immigration into one that President Donald Trump eagerly exploits during his 2020 re-election bid.

Senators Bernie Sanders, Elizabeth Warren and Kamala Harris are among the leading candidates who’d make illegally crossing the border a civil rather than a criminal offense. On that point they’re at odds with front-runner Joe Biden and several other centrist contenders, some of whom warn that Democrats are handing Trump a gift.

The opposing viewpoints were on display during last week’s Democratic forums in Detroit.

“If a mother and a child walk thousands of miles on a dangerous path, in my view, they are not criminals,” Sanders of Vermont said on the first night of the debates. The following night Biden, the former vice president, said that, “If you cross the border illegally, you should be able to be sent back. It’s a crime.”

Democrats have hoped to use Trump’s harsh immigration policies against him as the backlash grows against the treatment of families at the border and potential raids in interior states to round up undocumented immigrants. But most voters are cool to the idea of decriminalization, and Trump could use the issue to brand all Democrats as “soft on crime” and favoring “open borders.”

Central to Appeal

A promise to stem illegal immigration and tighten U.S. borders was central to Trump’s appeal in 2016. The president’s actions in office, including diverting Pentagon money to build his promised wall on the U.S.-Mexico frontier, separating parents and children in border detention facilities, and banning travel to the U.S. from several majority-Muslim nations, have kept the issue on the front burner.

In a Gallup survey taken in July, 23% of Americans surveyed said that immigration is the most important problem facing the country, the highest percentage since the polling group first measured the issue in 1993.

“The greatest betrayal committed by the Democrats is their support for open borders,” Trump told the crowd at a rally in Cincinnati on Thursday. “And these open borders would overwhelm schools and hospitals, drain public services and flood communities with poisonous drugs.”

Clear Divisions

Joe Trippi, a veteran of Democratic presidential campaigns who isn’t aligned with any of the current candidates, said there are clear divisions within the party about the wisdom of pushing to decriminalize border crossings by undocumented migrants.

“There’s no position you can take that would not have Trump making that attack,” he said. “The question is what seems reasonable and right to the American people.”

There are other significant issues dividing Democrats -- including Medicare for All and the Green New Deal -- but few are as widely unpopular as decriminalizing border crossings. A July 15-17 NPR/PBSNewsHouse/Marist Poll found that 66% of Americans think it’s a bad idea, and just 27% support it. Even among Democrats a minority -- 47% -- supported it, while 87% of Republicans were opposed.

Call for Repeal

White House hopeful Julian Castro raised it during the first round of Democratic debates in June, calling for repealing a section of the Immigration and Nationality Act that allows crossing the U.S. border illegally to be prosecuted as a misdemeanor, punishable with up to six months in prison.

That’s enabled the separation of families at the border as the Trump administration prosecutes migrant parents crossing with their children, who are put in the hands of civil immigration authorities.

At the latest debates, Castro, Warren of Massachusetts and three other candidates -- California’s Harris, Senator Cory Booker of New Jersey, and Senator Kirsten Gillibrand of New York -- took the strongest positions for decriminalizing border crossings. Booker said if cases were moved through civil courts, “You won’t need these awful detention facilities that I have been to; seeing children sleeping on pavement, people being put in cages, nursing mothers, small children.”

Warren argued that ending criminal penalties is a moral imperative, saying that “laws matter. And it matters if we say our law is that we will lock people up who come here, seeking refuge, who come here, seeking asylum. That is not a crime.”

Trump’s Trap

That drew warnings from some of the other candidates. Montana Governor Steve Bullock said decriminalizing unauthorized entries and giving health care to undocumented immigrants -- a policy advanced by Sanders -- was “playing into Donald Trump’s hands.”

“We’ve got 100,000 people showing up at the border right now,” Bullock said. “If we decriminalize entry, if we give health care to everyone, we’ll have multiples of that.”

Biden and South Bend, Indiana, Mayor Pete Buttigieg tried to hit a middle ground. Biden said current law doesn’t need to be changed, since it allows migrants to legally seek asylum in the U.S. The problem, he said, is the Trump administration’s application of the law.

“The only reason this particular part of the law is being abused is because of Donald Trump,” Biden said. “We should defeat Donald Trump and end this practice.”

Don’t Take Bait

Castro called the open borders tag “a right-wing talking point, and franklyI’m disappointed that some folks, including some folks on this stage, have taken the bait.”

Neil Sroka, spokesman for the progressive activist group Democracy for America, said Trump will tag any Democrat as favoring open borders, regardless of the person’s position. The party’s nominee should tap into the enthusiasm of left-leaning voters by proving a “crystal clear contrast” with Trump by supporting decriminalization of undocumented border crossings, Sroka said.

Still, Domingo Garcia, national president of the Latino civil rights group LULAC, said Democrats would do better to stress comprehensive reforms that could include a pathway to citizenship and a system that also requires migrants to live by some rules.

‘Free Stuff’

“Democrats have to be careful of not being portrayed as the party of open borders and the party of giving free stuff away to every immigrant that crosses the Rio Grande or overstays a visa,” Garcia said. “They have to make it clear that any immigration reform will require immigrants to pass criminal background checks, pay fines, learn English and be embedded before they become permanent legal residents and eventual citizens.”

Some prominent Republicans said they watched the Democrats debate on immigration with glee.

“It’s a real problem for Democrats to take positions that are so far out of the mainstream of even their own party, let alone the nation,” said Senator Mitt Romney of Utah, the 2012 GOP presidential candidate. “I am delighted that they’re making it so much easier for Republicans.”

Senator John Cornyn, a Texas Republican, said Democrats were embracing policies that might encourage more illegal immigration, a notion that he said would turn off voters in swing states.

“They may elect Trump,” Cornyn said. “The president has his admirers and his detractors, but they’re going to make themselves the unacceptable alternative.”

To contact the reporter on this story: Laura Litvan in Washington at llitvan@bloomberg.net

To contact the editors responsible for this story: Joe Sobczyk at jsobczyk@bloomberg.net, Wendy Benjaminson, Ros Krasny

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