Court filing alleges DHS used Palantir-built database to track and intimidate ICE protest observers

A newly unsealed court filing alleges that US Department of Homeland Security (DHS) agents created dossiers on observers of ICE activity in Maine and stored the information in a Palantir-built database called the Investigative Case Management (ICM) system.

According to the filing, agents labeled at least two observers as 'Threat to Law Enforcement, Professional Protestor' in ICM records, shared their photos with a Customs and Border Protection (CBP) officer for facial recognition searches via an app called Mobile Query, and ran license plate lookups to gather additional personal data.

The filing describes an incident where an agent identified only as 'Agent J.C.' called one observer, Carlyn Williams, after running her license plate and photo through law enforcement databases, warning her that people who 'do this' might be added to a domestic terrorism watchlist and that she could be arrested if she continued observing ICE activity.

Plaintiffs in the case, which was filed under seal in September 2025 and unsealed in October 2026, allege the conduct had a chilling effect on their First Amendment rights, with observers stopping their monitoring activities after the alleged intimidation.

The lawsuit seeks to bar DHS from using the collected information against the plaintiffs, order that Williams’ records be archived, and prohibit agents from threatening observers with watchlists or following them to their homes.

DHS has called the case 'meritless' and denied maintaining a database of domestic terrorists, while ICE awarded Palantir the original ICM contract in 2014 and a five-year support contract valued at up to $96 million in 2022, with an additional $30 million added in 2025 for a new platform called 'ImmigrationOS.'

The ICM system is built on Palantir’s Gotham software and automatically shares subject records with CBP’s TECS system, where they act as 'lookout records' for border screening, according to a 2016 DHS privacy assessment cited in the filing.