How The Banner tracked thousands of immigrants held by ICE

The Banner set out to measure how much the surge in activity by federal Immigration and Customs Enforcement under President Donald Trump has changed immigration detention in Maryland and the lives of thousands who have passed through it.

As the number in custody ballooned, lawyers told us their clients were moving much farther away, introducing new administrative and legal hurdles to their cases. Those detained said the extra distance from family exacts a deep psychological toll.

We found that people detained in Maryland and other states without long-term detention facilities are transferred more and travel farther than their counterparts elsewhere.

More than 1 million stays in detention

Our analysis relied on detention records obtained through a lawsuit by the Deportation Data Project, a group of lawyers and academics working to make ICE’s own raw data public. Unique identifiers assigned to detainees allowed us to track more than a million people’s movements in immigration detention.

Records included details of each person’s time in custody, including when their detention started. Those dates were then matched to which president was in office during their time in ICE custody.

Although ICE’s data included the names of the facilities where they started and where they were moved, it did not provide the locations required to measure their distance from one another. To pinpoint the locations and distances between them, we used databases of ICE facilities compiled by the Vera Institute of Justice, a nonprofit criminal justice advocacy group, and the Deportation Data Project.

After spot-checking our database against official ICE records and satellite imagery, we combined it with the ICE detention records, identifying matching facilities for more than 99% of detainees and excluding the handful who had stints at facilities that did not match any in our records.

We measured the straight-line distance between the facilities where each person was detained. It’s worth noting that people likely traveled even farther than this approach estimates. Driving distance and airplane routes can add significant mileage. We calculated the total distance traveled by each detainee by adding the distances between each facility they were held in.

We found that the big difference for Marylanders under Trump is how far they’re being transferred. A person first detained in Maryland typically moved more than 1,200 miles, roughly the driving distance between Baltimore and southern Louisiana. During a similar period under former President Joe Biden, that person would have moved roughly 700 miles.

How Maryland compares

Maryland is one of a handful of states without a long-term ICE detention facility. Our analysis found that, even before Trump took office, those detained in the state were being transferred between facilities more often than those elsewhere. Under Biden, this usually meant a transfer to a larger facility in Pennsylvania or Virginia.

Amid the Trump immigration crackdown, we wanted to know if those detained in Maryland were destined to move farther than people held in states with long-term facilities that could more readily house them.

Initially after an immigrant is arrested, ICE confines them at one of two Maryland short-term facilities: a small hold room at the George H. Fallon building in Baltimore or another at a federal office in Salisbury. Based on facility-type definitions published by TRAC, an independent research group, we decided to compare the state to others that had only hold rooms or short-term processing facilities — both of which are designed to keep people for fewer than 24 hours.

Because facilities open and close over time, we decided to limit our research to a two-year span covering the last year of Biden’s administration and the first year of Trump’s. We used a combination of documents the agency posts online, detention records and news stories to identify the states that had only hold rooms or short-term processing facilities from January 2024 to January 2026: Maryland, Oregon, Illinois, Connecticut and Delaware.

We found the typical person who began their detention in a state without a long-term facility traveled roughly seven times farther than someone who began in a state that has one.

To separate the effects of presidential administrations and the presence of a long-term facility, we used a statistical model. To build and evaluate that model, we consulted Dan Naiman, a professor of applied mathematics and statistics at the Johns Hopkins University.

The regression analysis confirmed our findings: People in states without long-term detention facilities were being moved farther — regardless of who was president.

But administrations matter, too. Those detained under Trump traveled nearly seven times farther than those detained under Biden.

We also found that those detained in states with a long-term facility were more likely to be held in just one place. Nearly a third never moved from the facility where they were first detained. In states like Maryland, this was much rarer.

For the details of our data analysis, visit our GitHub.