Last month, Colleen Fagan was observing an immigration enforcement operation at an apartment complex in Portland, Maine, when federal agents scanned her face with a smartphone and appeared to record her car license plate number.In a social media video she recorded, Fagan can be heard asking why the agent was taking her information. What the agent said next made the video go viral."Cause we have a nice little database," the masked agent said. "And now you're considered a domestic terrorist."Fagan, who is a social worker, has now joined a federal class action lawsuit that argues the Department of Homeland Security and a number of its sub-agencies are violating the First Amendment and are taking actions "designed to chill, suppress, and control speech that they do not like.""A federal agent called me a domestic terrorist just because I recorded agents operating in public in my community. But I have a right to do that, and so do others," Fagan said in a statement. "I want people to know how important it is to use our First Amendment rights to observe and document what is happening. Peaceful dissent is not a crime."Though Fagan's video went viral, her full name had not been widely publicized until this lawsuit. Related Story: NPRThe suit, filed by the legal nonprofit Protect Democracy and the law firms Dunn Isaacson Rhee and Drummond Woodsum, alleges federal agents are unconstitutionally retaliating against people who are lawfully observing and recording federal immigration enforcement operations by gathering their personal information and labeling them domestic terrorists."Plaintiffs must either abandon their constitutional rights or accept being cataloged and branded as 'domestic terrorists,'" reads the lawsuit, which was filed in federal district court in Maine on Monday. "That is a choice the Constitution does not require Plaintiffs, or anyone, to make."After the lawsuit was filed Monday, DHS told NPR in a statement: "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. Obstructing and assaulting law enforcement is a felony and a federal crime. Our law enforcement methods follow the U.S. Constitution."After federal agents fatally shot two U.S. citizens in Minnesota last month, DHS officials labeled both of them domestic terrorists in the immediate aftermath.Federal agents have access to facial recognition tools that can be used to identify people in the field, and the lawsuit also mentions the mobile app Mobile Companion by Motorola Solutions, which allows agents to use a smartphone to scan license plates.These kinds of surveillance tools have allowed federal agents to intimidate observers and protesters by revealing they know their names and addresses, the lawsuit says. Several Minnesota observers who have followed federal agents in their cars have described the experience of agents leading them to their own homes to show they know where they live. The lawsuit names other Maine observers who have had the same experience. Related Story: NPRIt is legal for observers to film and follow federal agents at a safe distance, Scarlet Kim, senior staff attorney with the American Civil Liberties Union's Speech, Privacy, and Technology Project, told NPR earlier this month. But dozens of people in Minnesota said in declarations collected by the ACLU that they were observing federal agents but were told they were impeding, interfering or acting illegally.Homeland Security Secretary Kristi Noem said at a press conference in July that violence against DHS agents "is anything that threatens them and their safety," and went on to say that included "doxing them" and "videotaping them where they're at when they're out on operations."DHS has crafted a wide definition of doxing. The department's then-spokesperson, Tricia McLaughlin, told The American Prospect in September that "videotaping ICE law enforcement and posting photos and videos of them online is doxing our agents."A memo issued by Attorney General Pam Bondi in December lists "doxing" law enforcement as domestic terrorism.Elinor Hilton, another resident of Portland, Maine, is also listed as a plaintiff in the new lawsuit. Federal agents captured her face and license plate with their phones on Jan. 21, after she began recording them conducting an immigration enforcement operation at a Home Depot, the lawsuit says.She says one told her, "I hope you know that if you keep coming to things like this, you are going to be on a domestic terrorist watchlist. Then we're going to come to your house later tonight," according to the lawsuit.Hilton did not stay at her home that night for fear the agent would make good on the threat, the lawsuit says. She has reduced how often she observes federal agents and no longer uses her own car when she observes. She now parks her car several blocks away from her home and those of family members "out of concern that federal agents might recognize her car and trace it to her home." She says on a recent trip she left her personal phone at home out of concern that if she was placed on a government list, federal agents might detain her and search her phone.Fagan is concerned about being placed on a "no-fly" or similar list, the lawsuit says, and worries her current or future employment could be affected by any labels DHS gives her.Less than a week before Hilton's interaction with federal agents, Tom Homan, President Trump's immigration adviser, told Fox News host Laura Ingraham that he wanted to create a "database" of people who impede ICE."These people who want to say follow ICE and film ICE, you know what, you can protest, they have that right." Then he added that for those who cross a legal line, "We're going to create a database where those people that are arrested for interference, impeding, and assault, we're going to make them famous," Homan said. "We're going to put their face on TV. We're going to let their employers, in their neighborhoods, in their schools, know who these people are."But in other public appearances, federal officials have denied a database of protesters exists.At a congressional hearing earlier this month, U.S. Rep. Lou Correa (D-Calif.) asked Todd Lyons, acting director for U.S. Immigration and Customs Enforcement, to respond to what the federal agent in Maine said about "a little database" in the video Fagan recorded."I can't speak for that individual, sir," Lyons said. "But I can assure you that there is no database that's tracking United States citizens."The lawsuit says, "If Defendants' denials are true—and the actions captured on video simply involved federal agents pretending to add observers to a database—then they are deliberately lying about domestic terrorist watchlists or databases to unlawfully intimidate observers."The lawsuit is asking a federal judge to stop DHS from collecting records on people and from "threatening, harassing, and otherwise retaliating against" them for exercising their protected first amendment rights, and to expunge records that have already been collected.JoAnna Suriani, counsel at Protect Democracy, said the lawsuit will "ensure that the federal government can no longer use unconstitutional surveillance tactics to silence its critics and sideline the observers who protect our communities." Transcript JUANA SUMMERS, HOST: People who film immigration operations in their cities say federal agents are surveilling and intimidating them. In some cases, they say agents have threatened to add them to a list of domestic terrorists. A new lawsuit filed in Maine against the Department of Homeland Security argues this pattern violates the First Amendment. NPR's Jude Joffe-Block has been following the case and joins us now. Hi.JUDE JOFFE-BLOCK, BYLINE: Hi.SUMMERS: So, Jude, these people who are observing and recording federal agents, what do they say is happening to them?JOFFE-BLOCK: Well, one of the plaintiffs in this case is Colleen Fagan. She's a social worker in Portland, Maine, and last month, she noticed federal immigration agents in an apartment complex parking lot. She had her phone out recording them when she noticed the agents were seemingly recording her. One held up his phone to her face. A second one seemed to be recording her car's license plate. That's according to her account and video she took. Here's an exchange she had with that agent that she recorded.(SOUNDBITE OF ARCHIVED RECORDING)COLLEEN FAGAN: It's not illegal to record.UNIDENTIFIED AGENT: Exactly.FAGAN: Yeah.UNIDENTIFIED AGENT: That's what we're doing.FAGAN: Yeah. Why are you taking my information down?UNIDENTIFIED PERSON: What you guys doing over here?UNIDENTIFIED AGENT: 'Cause we have a nice little database.FAGAN: Oh, good.UNIDENTIFIED PERSON: Listen, we out here just (inaudible).UNIDENTIFIED AGENT: And now you're considered a domestic terrorist.JOFFE-BLOCK: It's hard to hear, but the agent says we have a nice little database, and now you're considered a domestic terrorist. And this video was really shared widely because this comment was so stunning.SUMMERS: Yeah, I remember coming across it myself, but I want to ask. Is the federal government really putting observers like Colleen Fagan into a database of domestic terrorists?JOFFE-BLOCK: Well, the Department of Homeland Security told us there is no database of domestic terrorists run by DHS. The statement goes on to say that the agency does, quote, "monitor and investigate and refer all threats, assaults and obstruction of our officers to the appropriate law enforcement," and they say their methods follow the Constitution.This video that Colleen Fagan recorded actually came up in a congressional hearing earlier this month. ICE acting director, Todd Lyons, was asked about it. He said he couldn't speak to what the agent says in the video, but he said, quote, "I can assure you there is no database that's tracking U.S. citizens." But other outlets have reported on what appear to be efforts by DHS to collect information on protesters. CNN reported last month on a memo to that effect. And one thing this lawsuit seeks to do is understand what exactly is happening with the images and information that federal agents appear to be collecting on observers and protesters.SUMMERS: What are the specific legal concerns here?JOFFE-BLOCK: Well, this is about free speech, and this lawsuit alleges that DHS is violating the First Amendment. I spoke with one of the attorneys on the case, JoAnna Suriani with Protect Democracy. It's a nonprofit legal and advocacy organization.JOANNA SURIANI: Having your data collected and maintained by the federal government when all you were doing was expressing a view and observing law enforcement behavior in your community, it chills your right to speak out in the future in a few ways.JOFFE-BLOCK: She says observers may not feel comfortable continuing to exercise their right to observe. And according to the lawsuit, Colleen Fagan, for example, has wondered, after that exchange, where she was told she was considered a domestic terrorist, if she was going have trouble flying or if her employment could be affected.SUMMERS: Right. So what about other places? Are we seeing this occurring outside of Maine?JOFFE-BLOCK: Well, yeah, the American Civil Liberties Union has brought a lawsuit in Minnesota against DHS that has some overlap. There are several observers there who've described following federal agents in their cars to observe them only to have the federal agents lead them to their own homes. Basically, the federal agents are showing they know who the observers are and they know where they live. And we know these federal agents have a lot of tools, including surveillance technology at their fingertips to identify people.SUMMERS: NPR's Jude Joffe-Block, thank you.JOFFE-BLOCK: Thanks, Juana.