In the days after Donald Trump won November’s presidential election, immigration and civil liberties advocates began assessing how the new president might carry out his promises to create a registry of Muslims and deport millions of undocumented immigrants. Almost immediately, it became clear the Trump administration would need data, and a lot of it, in order to not only peg people’s religious affiliation and immigration status but also allow federal agents to verify their identities and track their whereabouts. Information that could be used for such purposes is collected and stored by a variety of state agencies that issue driver's licenses, dispense public assistance, and enforce laws.

On The Record This piece is part of an ongoing series in which The Verge asks state officials where they stand on sharing immigration data with the federal administration. This piece is part of an ongoing series in which The Verge asks state officials where they stand on sharing immigration data with the federal administration.

Just three days after the election, New York City mayor Bill de Blasio made headlines by proposing a plan to keep data out of Trump’s hands by deleting information contained in a database of municipal ID cards that had been marketed to undocumented immigrants in the city.

Now, in the first weeks of the Trump’s presidency, the battle over the federal government’s access to locally held data has gone national.

In Washington state, The Verge has learned, Democratic governor Jay Inslee has directed members of his policy and legal staff to work with a handful of state agencies to identify data that could be utilized by Trump’s deportation officials, and how, if possible, to shield any such information from federal authorities engaging in mass deportation. In California and New York, Democratic lawmakers have proposed legislation to block state data from federal immigration authorities. Democratic legislators have also proposed bills in Washington state, California, New York, and Massachusetts that would prevent state data from being used by federal authorities to build a registry of people belonging to a certain religion.

The battle over the federal government’s access to data has gone national

And it’s not only Democrats who are contemplating how to handle state data under Trump. On Monday, Vermont’s Republican governor Phil Scott condemned President Trump’s recent immigration order and called for the convening of a “civil rights and criminal justice” task force to identify state and federal laws Trump’s orders might be breaking and to recommend any action the state can take. A spokesperson for the governor told The Verge that Governor Scott is aware of concerns over the state’s data being potentially shared with Trump’s immigration officials and says that the governor’s civil rights task force would discuss the matter.

The Verge is reaching out to governors and legislators across the country to ask what, if anything, they’re doing to keep their data from being used for mass deportation or the building of a muslim registry. This story is the first in a series, which we will update as more states confirm or deny plans to block federal access to databases that could be used for deportation or registries.

The efforts could lead to a showdown between state and federal authorities

The efforts that are emerging could lead to a showdown between state and federal authorities, who may require state data to fulfill the Trump administration’s agenda. Data gleaned from state agencies can be an important component of carrying out the federal government’s deportation program, says Anil Kalhan, a law professor at Drexel University who has extensively studied surveillance systems related to immigration enforcement.

“The reason why federal authorities want to access information from state and local officials is because their personnel and resources are limited,” says Kalhan. “The logic of doing this is that it essentially creates border checkpoints all over the place. So when a person is going about day-to-day life and interacting with the police or applying for a driver’s license or for social service benefits — that effectively becomes an immigration screening opportunity.”

In Washington state, Governor Inslee has launched his review of state data by primarily focusing on two agencies: the state’s Department of Motor Vehicles (known as the Department of Licensing) and the state’s Department of Social and Health Services. Nick Brown, general counsel for Governor Inslee, tells The Verge that, in the office’s initial assessment, these two agencies appeared the most likely to contain the potentially relevant data. The state would not block information sharing between any federal law enforcement agency, Brown said, in the case of a genuine threat to public safety. Brown says the review could likely expand to the Washington State Health Care Authority and possibly other agencies that provide public assistance and might collect personal information and indicators of citizenship status.

“It essentially creates border checkpoints all over the place.”

“It’s certainly a question that we’re digging into,” said Brown. “My guess is that it will likely be limited to agencies that provide public benefits.”

Brown says that, because the Washington State Patrol generally uses a federal database for arrest information, the state appears to have little control over what information its police force shares with federal authorities. Kalhan says this is likely the case across the country: most criminal justice data key to the deportation of immigrants who have been been incarcerated is provided to Immigration and Customs Enforcement (ICE) through the FBI’s National Crime Information Center, a national clearinghouse for arrest data.

Yet states like California and Connecticut, according to public records, do maintain law enforcement databases that state officials have allowed ICE to access directly.

Although the exact extent of direct data-sharing between states and federal immigration authorities remains murky, some glimpses of these programs have emerged in public records, and immigration advocates see any state database that contains information that would be useful to Trump’s deportation plans as a potential point of vulnerability.

State DMVs have worked directly with ICE

State DMVs, for instance, have worked directly with ICE to provide information to the agency’s Enforcement and Removal Office, the country’s primary deportation force, according to the National Immigration Law Center.

In California, federal immigration authorities have utilized a state database of suspected gang networks to arrest and deport suspected gang members. Critics have argued that the database appears flawed and might ensnare innocent people in ICE’s deportation proceedings.

A pending bill in California would put an end to this sort of collaboration between those state and federal agents by outlawing “anyone or any entity” to use a database maintained by a state agency “for the purpose of immigration enforcement.”

“To the millions of undocumented residents pursuing and contributing to the California Dream, the State of California will be your wall of justice should the incoming Administration adopt an inhumane and over-reaching mass-deportation policy,” Senator Kevin de León, the author of the bill, said in a statement. “We will not stand by and let the federal government use our state and local agencies to separate mothers from their children.”

“The State of California will be your wall of justice.”

On Monday, a Democratic state senator in New York proposed a bill that would limit both the state and New York City’s public university systems from compiling data on the number of foreign students enrolled, the programs that such students are enrolled in, as well as the collection of data about students’ nationality and immigration status. A bill introduced in the State Assembly prohibits the state from supplying any data to help the federal government create a registry of people based on race, religion, or nationality.

Similar bills targeting potential registry data have been proposed in California, Washington state, and Massachusetts.

The sponsor of the Massachusetts bill, State Senator Jamie Eldridge, tells The Verge that he has identified the state police and the state’s Department of Motor Vehicles as the agencies that house the most data that could be used to build a registry of Muslims. While he might have little ability to stop the Trump administration from building such a registry, Eldridge says, his state can at least refuse to participate.

“State tax dollars and resources should be not going to aid abetting that effort if it’s contrary to our values in Massachusetts,” Eldridge said. “And we believe it is.”