Donald Trump’s immigration policies would use local police to initiate mass deportations.

The largest mass deportation in American history begins on January 20th.

That’s what Donald Trump says. It’s a promise to remake American society in such fundamental ways, and Trump has so refused to explain it in detail that it’s hard to say whether he has the discipline to try. News junkies from the first Trump administration are well-versed in this grim guessing game: Since the guy lies constantly and says the first thing that comes to mind, how do you know when to take him seriously? He also promised mass deportations in his first administration, but his record was indistinguishable from Barack Obama’s, and it was his cruel and illegal tactics that drew attention.

But the next Trump administration appears to be better prepared, with less regard for the law and fewer opponents within his own party. Furthermore, polls suggest his anti-immigrant stance is widely shared – how many suburban Poles will want to proclaim their sanctuary city status this time?

Expect retaliation for controversial Trump-era policies like separating children from their parents at the border; the “Remain in Mexico” policy, which forced asylum seekers to live in Mexico while awaiting a court date; the Muslim ban, which excluded newcomers from a handful of countries in the Middle East and North Africa; a resumption of Immigration and Customs Enforcement raids on workplaces such as dairy farms and chicken factories; a new commitment to the border wall; and an end to refugee resettlement programs and Temporary Protected Status, the program that brought Haitian families to Springfield, Ohio.

But the most ambitious part of the Trump agenda is a promise to herd the country’s estimated 12 million undocumented immigrants into detention camps for deportation. This would result in millions of American children being separated from their foreign-born parents, permanently damaging key industries such as agriculture and construction, and literally decimating the populations of cities like Houston and Los Angeles. JD Vance said more than 500,000 Deferred Action for Childhood Arrivals recipients, Americans brought to the country illegally as children, could also be targeted – a betrayal for those who have trusted the federal government with their information.

Some of Trump’s advisers have pondered how the country could carry out a trillion-dollar policing operation without historical precedent. This includes staffing the State Department with ideological allies who pressure foreign governments to accept deportees; Reallocating ICE’s resources to Homeland Security Investigations, which focuses on cross-border crimes such as drug smuggling and human trafficking; calling up the National Guard; and the construction of hundreds of detention camps and the hiring of tens of thousands more law enforcement officers. The final part would require money from Congress and could take years.

By far the greatest resource Trump can use on his behalf is local police, whose cooperation with ICE (or lack thereof) was a constant struggle during his first term as “Sanctuary City” became an anti-Trump rallying cry .

If you want to see what the future holds, keep an eye on Arizona. Voters approved a ballot proposal that would allow local and state police to arrest and detain people based on their immigration status and state courts to deport them. The law is similar to Texas’s SB 7, which is in court because it appears to replace federal authority over immigration.

Also in Arizona, the winner of the sheriff’s race in Maricopa County (the fourth-largest county in the country, home to Phoenix) is a career cop named Jerry Sheridan, who was former Maricopa Sheriff Joe Arpaio’s right-hand man and would be considering himself a “constitutional sheriff” – an extremist view that sheriffs can defy the orders of courts or state officials if they feel they are defending the Constitution.

Sheriff Joe is a name that even casual observers might remember: Arpaio had a deal with the federal government that turned Phoenix-area police officers into immigration agents who, according to a 2011 Justice Department investigation, conducted “sweeps” in Latino neighborhoods “conducted to arrest undocumented immigrants through traffic stops. During this time of high-risk racial profiling, Latino drivers were nine times more likely to be stopped than non-Latino drivers. Following that report, the Obama administration suspended the county’s federal agreement, and Arpaio was later convicted of criminal contempt before being pardoned by Donald Trump. A related lawsuit cost Maricopa taxpayers more than $300 million, and the sheriff’s office is still under federal oversight.

Arpaio’s municipal border patrol law was made possible by a contract between local police and DHS called a 287(g) agreement. Originating from the 1996 immigration law, these agreements became widespread after the September 11 attacks, and by 2013, local law enforcement was responsible for initiating more than half of deportations outside the border.

After the Maricopa County scandal, the tide turned against 287(g). Obama reduced the program so that police could only investigate immigration status after an arrest or after receiving a warrant from ICE. Some sheriffs rejected the agreements entirely, saying they fueled distrust and discouraged immigrants from calling 911. After Trump’s election in 2016, many Democrats from big cities and blue states said they would pursue “sanctuary cities.” “Local law enforcement will not do the job of federal immigration enforcement,” Denver Mayor Michael Hancock told me in 2016. “That is not our responsibility.” Within five days of taking office, Trump issued an executive order alongside Attorney General Jeff Sessions , to withhold federal funding from these places. That was declared unconstitutional two years later.

But in reality, these high-profile performances by Resistance Democrats masked a trend: The number of jurisdictions with 287(g) contracts rose from 37 in 2017 to 140 in 2021. After years of declines, a Washington Post investigation found that the number of Arrests in 287(g) counties reached their highest level in a decade in 2019. The data seemed to confirm what civil liberties advocates have long argued: Even if immigration checks are conducted only in prison, police have wide latitude in deciding who to arrest. A previous study by the Migration Policy Institute found that half of all ICE referrals under the program went to immigrants who had committed misdemeanor or traffic violations. A grandfather who had lived in the United States for two decades could be deported because of a broken taillight.

In the heady pro-immigrant atmosphere of January 2021, newly elected sheriffs like Craig Owens in Cobb County, Georgia, and Kristin Graziano in Charleston County, South Carolina, boasted about ending their 287(g) programs and the Biden administration had stopped making his successes known. But this year, public opinion had changed dramatically: Owens, who won re-election, had to insist that he was indeed cooperating with ICE. Graziano lost to a Republican who had promised to do so.

Just as Arpaio had Arizona’s SB 1070, the boycott-inducing “immigration checkpoint at a traffic stop” law, Republican Sheriff-elect Sheridan might have Proposition 314 until the Texas law is viable.

Meanwhile, Trump’s team has again threatened to withhold federal funds from cities and states that do not comply with his deportation mandates. Immigrants in Aurora, Colorado, for example, where Trump has announced the mass deportation campaign will begin, are protected by a 2023 law that bans local cooperation with ICE. Project 2025 proposes to go further and require these jurisdictions to provide “full information sharing,” including access to voter registration and DMV databases. This was illegal last time, but it remains to be seen what a Trump Justice Department will make of these precedents.

Either way, Trump will launch another round of aggressive sheriff recruitment like he did in 2017. Mark Morgan, who served as Trump’s acting commissioner of Customs and Border Protection, told Stateline that the success of Trump’s plan depends on local law enforcement finding a way to do immigration work. And that means finding a reason to stop people.

“Everything is illegal,” a Connecticut state trooper once told me. “No front panel. License plate cover. Tinted windows. Too close. I won’t tow more than 300 cars. That’s not what people want.”

Unless they voted for it It.

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