President-elect Donald Trump has vowed to ramp up immigration enforcement on taking office and to launch a mass deportation operation that could affect a record numbers of migrants.

The US Department of Homeland Security estimated there were 11 million immigrants lacking a legal status in 2022.

Trump wants to remove a million undocumented people a year, according to Vice President-elect JD Vance – and would begin his clampdown almost immediately upon taking office.

Yet while the Republican president-elect has said his ambitions are unprecedented in scope, he must still follow a specific process, as outlined in US law.

Moreover, the president cannot make any new laws – beyond the powers specifically given to him by the Constitution or Congress – by simply issuing an executive order.

What’s deportation

Deportation entails the expulsion of immigrants.

The United States typically enforces it on those who entered the country illegally, violated its laws, overstayed a visa or are deemed a threat to public safety.

Most deportations are for civil immigration infractions rather than criminal violations.

Deportation figures have fluctuated significantly over the years, exceeding 100,000 a year in the mid-1990s and mostly rising ever since.

Trump deported some 1.5 million people in his first term of 2017 to 2021, a figure nearly matched under outgoing President Joe Biden – including a record 271,000 in fiscal year 2024.

How does it typically work

Anyone facing deportation must first be found, then detained and their immigration status verified by the government.

Trump’s threat of mass deportation would thus likely begin with raids or expansive search operations and some form of large-scale detention, requiring hundreds of thousands of beds.

Private prisons could be used or set up, along with temporary tent cities.

Most of those deemed eligible for deportation would then go before an immigration judge where they can defend their case.

During this process, immigrants can also opt to apply for a new immigration status, perhaps citing a family relationship or a fear of persecution back home.

The judge’s eventual ruling can also be appealed, potentially stretching the judicial process by weeks or years.

Some immigrants can also be subject to “expedited removal” without any hearing if they entered the United States without valid documents or broke their visa requirements.

Such decisions can’t be appealed, although the detainee can still apply for asylum.

Tens of thousands of people have been removed under this process each year since it began in the mid-1990s.

Where do deportees get sent

If a judge orders a deportation, the person can still leave voluntarily before the order is executed, a process called voluntary departure.

Each year, about 2% of people who face possible deportation take this route, seeking to leave without a formal order on their record and thus keeping open the possibility of returning to the United States in the near future.

Otherwise, federal officials can remove a deportee at any time once an order is signed and if a country has accepted them.

Complications can arise if the United States has strained relations or no diplomatic ties with a deportee’s home nation.

Migrants who cannot be deported can be detained for 180 days after a final removal order. They can also be released until deportation is possible.

Exceptions within standard process

In general, non-citizens who cannot be deported include asylum seekers, victims of crime, people with US family ties and whistle-blowers who report US labour violations.

Migrants with “Temporary Protected Status” are also exempt as they come from a land deemed unsafe, mainly due to natural disasters or conflict.

Temporary Protected Status lets immigrants work legally in the United States.

Protections are also offered to those who were brought into the country illegally as children.

Migrants in each of these categories can still be deported if they break the law.

Where could Trump make changes

“Safe” places that have not seen immigration raids in the past – such as schools or churches – could now come into play.

Incoming Trump officials say that workplace immigration raids, a policy Biden ended, may also become key.

Trump has said he will use the US military to the fullest extent of the law to support his efforts, deploying the National Guard to support deportations, but not make arrests.

“Sanctuary” jurisdictions that do not cooperate with federal immigration officials could also be targeted, perhaps threatened with a cut-off in federal funds should they not fall into line.

Trump could also end programmes that offer temporary protections to people fleeing violence or natural disaster, including those eligible under the TPS scheme.

As of March 2024, Temporary Protected Status covered more than 863,000 people from 16 countries.

People brought in illegally as children, estimated at more than half a million, could also face a new threat.

Trump expanded “expedited removals” in his first term, making for longer detentions and affecting more migrants.

Immigration advocates worry this policy may now be back.

A shortage of detention facilities could yet block mass deportation efforts, but the new administration might also house detainees in parallel facilities, be it building “tent cities” or using private detention facilities.

The chosen destinations for deportees could also change, should their home countries say “no” to a return.

During the first Trump administration, officials sent some asylum seekers to Guatemala.

Now, the new administration may be looking at a new list of target destinations, including Panama and the Bahamas.

This article first appeared on Context, powered by the Thomson Reuters Foundation.