Thirty-four members of Congress are demanding that the Department of Homeland Security and Immigration and Customs Enforcement provide detailed information about how tools developed by Palantir and “a range of surveillance companies” are fueling Trump’s ongoing immigration crackdown, according to a letter shared exclusively with WIRED.

On Thursday, the lawmakers sent the letter to DHS secretary Markwayne Mullin and acting ICE secretary Todd Lyons. It outlines significant concerns they have about how DHS uses software developed by Palantir, as well as facial recognition from Clearview AI, social media surveillance tools from PenLink, cell tower simulators from L3Harris, and and cellphone surveillance tech built by Paragon Solutions.

The lawmakers claimed that the suite of tools could be used to “compile, aggregate, and analyze large volumes of personal data and information,” and they questioned “what safeguards exist, if any, to prevent the misuse and collection of sensitive personal information.”

“These tools contribute to a mass surveillance ecosystem that appears to operate in conjunction with Palantir-developed platforms and ultimately support enforcement operations conducted by DHS, some of which target U.S. citizens,” the letter reads. It demands a response from ICE and DHS no later than April 24.

The letter included several specific questions about Palantir, including which “government and/or commercial datasets and information, if any,” are integrated into systems developed by the company. They also asked about a Palantir-developed app called ELITE, short for Enhanced Leads Identification and Targeting for Enforcement. Lawmakers requested a “comprehensive report” about the tool, including information about its development, its purpose, the specific categories it applies to data, and the current number of DHS officials authorized to use it.

New York Democrat Dan Goldman, a lead author on the letter, tells WIRED that he believes the second Trump administration has “weaponized” technology from Palantir in order to power its “inhumane mass deportation agenda” as well as “surveil Americans citizens.”

“The use of these tools raises serious concerns about civil liberties and privacy, yet DHS and ICE have thus far refused to provide transparency about how they are using these tools and what information they are collecting about American citizens,” Goldman says.

The letter’s focus on Palantir underscores how the Trump administration’s growing reliance on the company’s technology has become increasingly politically divisive. Palantir is a critical contractor for ICE and Customs and Border Protection, both of which are part of the Department of Homeland Security. WIRED previously reported that ICE currently uses several tools developed by Palantir. In addition to ELITE, Palantir built ICE’s “core law enforcement case management tool,” as well as the Immigration Lifecycle Operating System (ImmigrationOS), which immigration agents use to select deportation cases and track who has been deported.

Palantir’s revenue from government contracts has grown steadily since the company’s founding in 2004, and it increased during both Democratic and Republican administrations. Since the beginning of Trump’s second term, however, that business has exploded. The company earned a record of approximately $1 billion in payments and obligations from government agencies in the 2025 fiscal year, nearly twice as much as it earned the year prior.

In the letter, lawmakers also requested information about any “legal authorities” and internal policies that DHS uses to determine how the data it collects and aggregates is used, or how long it’s kept.

Lawmakers also asked whether DHS and ICE “collect or retain” the personal data belonging to US citizens, citing cases where US citizens encountered ICE and Border Patrol agents who then used facial recognition to learn the citizens’ identities. The lawmakers also asked if DHS has “collected or stored or otherwise processed information about individuals peacefully observing, documenting or protesting immigration enforcement operations,” and requested detailed information about any facial recognition tools used during immigration enforcement.”

Democratic representative John Garamendi, who signed the letter, tells WIRED that it’s “Congress’ duty” to rigorously oversee any potentially illegal surveillance of Americans. “As an out-of-control ICE terrorizes local communities and attacks American citizens, it’s increasingly clear that this alarming new reality demands action,” Garamendi says.