The Department of Homeland Security has repeatedly denied maintaining a database of U.S. citizen protesters or a database of “domestic terrorists.” In a statement to NPR, a DHS spokesperson said, “There is NO database of ‘domestic terrorists’ run by DHS. We do of course monitor and investigate and refer all threats, assaults and obstruction of our officers to the appropriate law enforcement.”

Lyons’ letter, dated April 21 and sent to Rep. Maxwell Frost (D-Fla.) and 11 other Democratic members of Congress, provides the most detailed public accounting yet of when and how ICE retains information on people who interact with its officers. The letter stated that ICE “does not maintain any kind of database of U.S. citizens protesting ICE activities” and that “DHS policies and practices are designed to respect lawful protests and constitutionally protected activities.” However, it added that at protests involving alleged criminal conduct, ICE collects “information to identify individuals reasonably believed to be involved in, or directly supporting, potential violations of federal law and to address officer safety and facility security concerns,” including “essential biographic and biometric information and situational details.”

“If individuals who interact with ICE officers are not arrested or detained, any information collected during those encounters is maintained consistent with applicable law and DHS and ICE policies and is treated as an official government record,” Lyons wrote.

The letter did not address what happens to that information after it is collected or how long it is retained, nor did it respond to questions about whether similar data collection occurs at other agencies within DHS. The letter from Frost and his colleagues was addressed to the Secretary of Homeland Security, but the response came only from ICE, raising questions about what may be happening in other parts of the department.

The acknowledgement matches the experience of Xenia Pantos and Carly Williams, a same-sex couple in Portland, Maine. Last January, Pantos said they stopped to observe federal agents conducting an immigration operation from about 10 feet away, did not interact with them, and noticed an agent photographing another observer’s license plate. Hours later, Williams said she received a call from a blocked number identifying itself as the Department of Homeland Security. The caller asked if anyone else drives her vehicle and, after she mentioned her spouse, said Pantos had stopped at the operation that morning. Williams recalled the caller saying, “You should let her know to not do that anymore because people who are doing that type of thing are getting added to a domestic terrorist watch list.”

DHS declined to comment on the couple’s account when asked by NPR. Pantos told NPR they felt too scared to observe ICE activity again after the call, worrying about their family’s safety. “We are a queer couple, which brings additional risks,” Pantos said. “There has been an ICE surge in Portland and I’ve felt really overwhelmed and powerless.”

Two months later, when the couple drove to Quebec City in Pantos’ car and re-entered the U.S., a Customs and Border Protection officer pulled them aside for additional questioning, took their phones and keys for about an hour, and asked Williams about her car registration even though they were in Pantos’ vehicle. Williams said the officer “seemed to be verifying what I was saying” while looking at a computer screen. The couple said the experience suggested their data had been retained in a federal system since the January encounter.

JoAnna Suriani, a lawyer at Protect Democracy who is representing Pantos, Williams, and other observers in a federal lawsuit, said the Lyons letter is “evidence of the fact that ICE is knowingly collecting and maintaining official government records on any protestor or lawful observer that its agents claim is potentially interfering with them or threatening agent safety.”

Scarlet Kim, a senior staff attorney at the American Civil Liberties Union who is representing observers in Memphis and Minneapolis in separate lawsuits, said the letter “strongly suggests” that even without a standalone database, federal agents are likely storing the information in existing data systems. Kim noted that the Trump administration has characterized First Amendment-protected activities such as video recording agents and sharing that information publicly as potential criminal acts. “So their own definition of what potentially violates the law and could trigger surveillance against an individual includes activities that are squarely protected by the First Amendment,” Kim said.

The letter was sent in response to a February inquiry from Frost and 11 other Democrats who asked broad questions about what data DHS collects on protesters. The lawmakers specifically asked whether DHS maintains or accesses lists or programs with code names including “Bluekey, Grapevine, Hummingbird, Reaper, Sandcastle, Sienna, Slipstream, and Sparta”—names reported in an independent journalist’s article as secret watchlists to track anti-ICE and pro-Palestinian protesters. Lyons’ letter said ICE does not use or access those programs.

Frost told NPR he plans to continue pressing the department. “That’s the concern, is that we have an agency that’s been tasked with immigration enforcement having a database … relating to Americans exercising the First Amendment, which is wrong,” he said.

At a congressional hearing the week of June 3, Homeland Security Secretary Markwayne Mullin said his department had used facial recognition technology on people gathered outside an immigration detention center in New Jersey that has been the site of recent protests. Mullin said, “If you verbally assault our officers, you go after our vehicles, you assault our property, you assault one of our officers, we will find you, we will arrest you.”

The organization FIRE, which advocates for freedom of expression, announced last month that it is suing DHS and ICE for access to records on whether the department is maintaining a database of protesters.