Trump's mass deportation plan could cost $300B, advocacy group says

President-elect Donald Trump's promise of mass deportation has some immigrants across the country fearing the worst.

They are taking Trump at his word when he told supporters in October at a rally:  "I will launch the largest deportation program in American history."

The backdrop of his news conference had signs that read "Immigrant Crime" and "Deport Illegals Now." 

Trump has yet to detail his plans for this promise. 

Political analysts believe Trump's administration will begin by targeting undocumented immigrants with criminal convictions.

Trump has also in the past proposed revoking citizenship and ending birthright citizenship, a move that would impact millions of people.

Trump’s two first picks for immigration policy jobs spent the last four years angling for this moment.

Stephen Miller, who is expected to be named the deputy chief of staff for policy, and Thomas Homan, the new "border czar," had critical roles in the first Trump administration and are unapologetic defenders of its policies, which included separating thousands of parents from their children at the border to deter illegal crossings. 

The effect, according to immigration attorneys, will wreak havoc on the country. 

"Mass deportation will be devastating to the economy, this country, to families," said Jose Osorio, an immigration attorney. "One of the plans is job site raids. If it gets to that point, people will be caught up in the system. How will they know who's an immigrant and who is not?"

Bill Hing, a University of San Francisco professor of law and immigration, added that he believes "we’re immediately going to see a termination of DACA," referring to the Deferred Action of Childhood Arrivals, a 2012 law that allowed certain immigrants who came to the United States as children temporary relief from deportation. 

The American Immigration Councill, a non-partisan advocacy group, estimates Trump's immigration proposals will cost taxpayers more than $300 billion. 

The Associated Press contributed to this report. This story was written in Oakland, Calif. 

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