How Trump can ramp up deportations

Donald Trump says one of the first things he'll do when he becomes president is deport up to 3 million undocumented immigrants. It would be one of the largest such roundups in American history.

Here are answers to many questions about how he will accomplish that.

How many "criminal" undocumented immigrants are there?

In a post-election interview with CBS' 60 Minutes, Trump said he would deport 2 million to 3 million of the 11 million undocumented immigrants who are "criminal and have criminal records." The actual number depends on how one defines "criminal."...

The Department of Homeland Security puts the number of "removable criminal aliens" at 1.9 million...

Many are already in custody, making them the easiest to identify....

How will the government track down those undocumented immigrants?

Trump could ask Congress for more funding to increase the size of Immigration and Customs Enforcement (ICE), but a quicker solution would be redirecting the current 14,000 ICE officers, agents and special agents to concentrate on arrests.

But only 1,000-1,100 agents currently down fugitive undocumented immigrants who are criminals or gang members....    The rest work on detention operations, screening visa applicants in foreign countries, conducting immigration audits of U.S. businesses and investigating crimes that include money laundering, import and export fraud, and human trafficking.

Sandweg said several core functions must be maintained because of congressional mandates, but an ICE director could easily refocus more people to finding undocumented immigrants.

"There would be a lot of flexibility for an ICE director to re-calibrate the agency," said Sandweg, now an attorney with Frontier Solutions.

How quickly can undocumented immigrants be deported?

Before they can be deported to their home country, immigrants have the right to a hearing before an immigration judge. But the nation's immigration courts are already overburdened.

That has led to a huge backlog of 521,676 cases waiting nearly two years on average to be heard, ...

The only way to speed up those cases is to hire more immigration judges....

Yet, even if Trump filled all 374 posts and added 150 more judges over the next two years, they could not clear out all the currently pending immigration cases until 2023, according to a review by Human Rights First, a non-profit advocacy group.

Which undocumented immigrants will be targeted?

Trump's emphasis on criminals may leave millions of other undocumented immigrants in the clear.

One such group: the 740,000 young undocumented immigrants granted deportation protections under President Obama's Deferred Action for Childhood Arrivals program, known as DACA. To qualify, they had to register with the federal government, have a clean record and work or go to school.

Trump has vowed to end the program and rescind their deportation protections, leaving them fearful of being targeted.

Mexican nationals would be the most heavily targeted, because they account for 52% of undocumented immigrants, according to the Pew Research Center. Another 15% come from Central America, 13% are from Asia, and 6% come from South America.

Deported Mexicans are usually sent home by bus, while those from other countries are put on flights.

What will happen to those who remain?

As a candidate, Trump often hinted that some undocumented immigrants could remain in the U.S. During the 60 Minutes interview, he said that after the border is secured, his border wall is completed and "everything gets normalized," he would "make a determination" on how to handle those who remain.

Trump has not elaborated, but Republican proposals in recent years provide some possibilities....