For Dana Briggs, a 71-year-old Air Force veteran, it was only natural that he would join a September demonstration outside a Chicago detention center. He has regularly protested the Department of Homeland Security’s actions for more than a decade.

But this time, he would find himself inside a federal prison hours later. He said that while at the demonstration, he had been knocked to the ground by agents, swarmed and arrested, and had been taken to a hospital, where he was handcuffed to a bed. He was then transferred to the federal facility, and read his rights, fingerprinted and photographed.

So by the time Mr. Briggs was ordered to take a cotton swab and rub it against the inside of his cheek, he complied.

“If you refuse to give a swab, you’re committing another crime,” Mr. Briggs said in an interview. “I was unaware of that. And I suspect that 99.9 percent of us in this country are unaware of that.”

This week, Mr. Briggs became the lead plaintiff in a lawsuit against the federal government’s DNA collection practice, arguing that his arrest and the collection of his sample violated his rights to protest and protections against the government conducting “warrantless, unreasonable intrusions” into his body.

The lawsuit, filed in the Northern District of Illinois, names three other people as plaintiffs, two of whom were arrested but never charged with a crime.

“The government’s chilling message is clear,” the suit says. “If you protest government policies, we will arrest you, file away your DNA and monitor you — and potentially your biological relatives — going forward.”

In a directive issued last year, U.S. Customs and Border Protection said that people who are arrested by its officers or who are facing charges or convicted must provide DNA samples. According to the directive, the agency will not use force to collect DNA samples but may refer people for prosecution if they don’t cooperate.

In Mr. Briggs’s case, he was released two days after his arrest, and the charges against him were dismissed two months later. The cases of four other protesters who were arrested that day were also dismissed. A federal judge found that the government “swung and missed — multiple times” in charging Mr. Briggs.

But while Mr. Briggs was freed, his DNA sample remained in federal custody.

Last year, Georgetown Law’s Center on Privacy and Technology found that DNA samples were collected from about 2,000 U.S. citizens who were stopped at border checkpoints from October 2020 to December 2024. In some cases, the report found, the agency collected the DNA without stating a reason for doing so.

And that was before the Trump administration’s immigration crackdown.

During President Trump’s second term, federal deployments have swept through major cities, leading to a wave of protests and clashes between immigration agents and demonstrators. Many protesters have been arrested, and while some were not charged with a crime or have had their charges dismissed, their DNA samples have been collected and stored.

The lawsuit asks that the Homeland Security Department — the parent agency of Immigration and Customs Enforcement — be forced to follow a 2013 Supreme Court ruling that limited DNA collection to suspects arrested in connection with serious crimes.

“It puts you and your family in a surveillance state database of people who’ve criticized this administration,” said Carey R. Dunne, a founder of the Free + Fair Litigation Group, which represents Mr. Briggs. He called the government’s actions “a constellation of constitutional violations that needed to be challenged.”

Mr. Dunne and Mark F. Pomerantz, another founder of the litigation group, had led the Manhattan district attorney’s investigation into Mr. Trump’s business practices. They resigned in 2022 and, with a third founder, formed Free + Fair, a nonprofit law firm that aims to stem the tide of what it describes as anti-democratic policies in the United States.

The federal government’s DNA collection practice, on an “authoritarian scale of one to 10, this is a 10,” Mr. Dunne said. In a statement Wednesday evening, the Department of Homeland Security said that the agency is required under federal law to collect DNA samples. The Department of Justice did not responded to a request for comment.

In the decades since DNA was introduced as evidence in criminal cases, law enforcement agencies across the country have come to rely on it, particularly in solving cold cases.

DNA can be collected through an array of methods beyond swabs of saliva. In New York’s Gilgo Beach murder case, investigators used a sample from a discarded pizza crust to connect Rex Heuermann to four bodies found in 2010 on Long Island. Law enforcement agencies, including D.H.S. and the Police Department, have faced lawsuits over their DNA collection practices.

Over the span of about a month last year, the Trump administration launched a crackdown on illegal immigration in Chicago called Operation Midway Blitz. Throughout the operation, protesters gathered outside the Broadview ICE Detention Center facility, which had become the centerpiece of the administration’s crackdown.

On the morning of Sept. 27, Mr. Briggs left his home in Rockford, Ill., and traveled to Chicago to attend an Indigenous festival. On his way home, “appalled” by the administration’s actions, he stopped by the detention center.

About two hours after he arrived, a field commander yelled at the demonstrators to clear the streets, Mr. Briggs recalled. Seeing no people blocking the federal agents’ path, Mr. Briggs asked, “Why?”

“It was only about maybe eight to 10 seconds between the command to clear the streets and when I actually got knocked on the ground,” he said. “So even if I had wanted, I really didn’t have time or the energy at that point to actually get my butt off the streets.”

Video showed federal agents swarming Mr. Briggs and arresting him. He was taken inside the detention center for several hours before being transported to Loyola University Medical Center for medical treatment. At about 1 a.m., the agents took him to a federal facility, where he was read his Miranda rights, photographed, fingerprinted and ordered to provide a DNA sample.

The genetic material was sent to an F.B.I. database called CODIS that was created to gather information about convicted criminals and missing people and to assess evidence from crime scenes. According to the lawsuit, people who have been arrested are responsible for making sure their DNA is removed from the database when their charges are dismissed. Studies have shown that in most states, only a handful of DNA profiles added to the database have been expunged, the suit said.

In Mr. Briggs’s case, the lawsuit challenges the legality of collecting DNA from people arrested for “nonserious offenses.” The lawsuit also asserts that federal officials could use the DNA to draw inferences about people’s relatives, who did not consent or do anything wrong.

According to the lawsuit, the F.B.I. recently reported that the federal government had amassed about 27 million DNA profiles in a variety of cases and is collecting almost 150,000 DNA profiles monthly.

“I just find this to be abhorrent,” Mr. Briggs said. “If we don’t have a right to our own selves, everything is going to break down.”

When congestion pricing went into effect in New York City almost a year and a half ago, residents in the South Bronx, which has some of the highest asthma rates in the United States, expressed concern about the consequences for air quality. Some predicted that drivers, in an attempt to avoid the toll to enter Manhattan, would take detours through their neighborhood, which is chock-full of major highways and bridges.

Now, a Columbia University study, relying on data from 19 sensors across the South Bronx, shows that overall fine particulate matter — tiny, toxic particles produced by burning fossil fuels — has increased since the start of the tolling program. According to Alexander De Jesus, a Ph.D. candidate and an author of the study, a 2 percent increase in particulate matter was detected in the South Bronx from 2024 to 2025, the first year of congestion pricing.

Researchers from Columbia and other universities worked with data from the South Bronx sensors over two years, comparing the 12 months before congestion pricing with the same period after the program started. They found elevated particulate matter levels throughout most of the neighborhood, especially near major expressways. Two sensors, one near a community garden, showed a decrease in particulate matter levels.

“While New York City’s congestion pricing policy has improved air quality in the congestion pricing zone, it worsened air quality in surrounding areas such as the South Bronx, probably due to traffic diversions,” said Markus Hilpert, an associate professor of environmental health sciences at Columbia’s Mailman School of Public Health and an author of the report.

A spokesman for the Metropolitan Transportation Authority, which oversees congestion pricing, vigorously questioned the study, saying it has yet to be peer reviewed and did not take into account smoke from wildfires that affected the city for about six days in 2025. (The study is still going through the peer-review process, according to its authors, who said they had controlled for factors such as wildfire smoke.)

“Reducing air pollution has always been one of the core goals of New York’s congestion pricing program,” Janno Lieber, the chief executive of the M.T.A., said in a statement. His remarks were released on Tuesday by Mayor Zohran Mamdani, who announced that the transit agency had dedicated $20 million to address asthma in the South Bronx.

According to an abstract of the South Bronx study, which is not yet available in its entirety, the increase in fine particulate matter “was statistically significant, although there was substantial variability in estimates across monitor sites.”

The study does not make a definitive link between the introduction of congestion tolling and the increased readings in particulate matter. But its authors said they had controlled for other factors that contribute to fine particulate matter pollution in the South Bronx, such as building heat, seasonality, weather fluctuations and traffic patterns. What was left, they said, was that 2 percent increase, which they attribute to the congestion pricing program.

Measuring air quality is difficult, scientists say, because of variability in atmospheric conditions. At least one year of data tracking weather fluctuations across four seasons is necessary to have a snapshot of air quality shifts. Even then, every year is unique, which makes it challenging to compare one year with another.

The city’s Department of Health conducted a three-month study that compared the spring of 2024 with the spring of 2025, before and after the start of the tolling program, and found “no significant change” in fine particulate matter around the region.

In a report released this year, the M.T.A. said that highway traffic had mostly decreased during the same time period covered by the Health Department study, including in the South Bronx.

In New York City, traffic accounts for just 14 percent of fine particulate matter; most of the pollution comes from buildings and other sectors. “The South Bronx is a densely populated area,” Dr. Hilpert said. “Very often you see schools and residential high-rises located just next to highways, so even a modest increase in air pollution can have significant public health impacts.”

The South Bronx is one of the poorest areas in New York City, with a median household income of about $32,000 and little green space. In contrast, the neighborhood has an outsize number of waste transfer stations and industrial warehouses, including Hunts Point, one of the largest food distribution centers in the United States, with almost 13,000 trucks coming and going daily. Asthma afflicts one out of five children in the South Bronx.

Congestion pricing, which charges most drivers up to $9 to enter Manhattan 60th Street and below, is funding about $70 million of mitigation efforts in the South Bronx. They include subsidizing asthma programs in the borough and replacing refrigerated diesel trucks that serve Hunts Point with hybrid versions or vehicles that run on cleaner fuels. In 2025, tolls generated more than $578 million in revenue for the M.T.A., which is using the money to upgrade subways and buses that many in the South Bronx rely on, the spokesman said.

Heralded as a success by political leaders and many environmental activists, congestion pricing has reduced the number of cars entering the central business district by 11 percent, or 73,000 vehicles, with the remaining traffic moving faster and more people opting for public transit. Air quality improvements are harder to discern. Some studies show much cleaner air, while others have found little to no difference.

For people in the South Bronx, any decrease in air quality compounds an already challenging pollution situation, according to neighborhood advocates and researchers, who want state and city authorities to adopt measures to mitigate any increase in particulate matter.

“We are calling on the M.T.A. to treat congestion pricing as a living policy, one subject to continuous, transparent evaluation in dialogue with the communities bearing its costs,” South Bronx Unite, a nonprofit focused on social, economic and environmental issues, said in a statement released on Tuesday. “To declare it a success while communities like ours see air quality getting worse is premature and unjust.”

Stefanos Chen contributed reporting.

Steven Roth, the chief executive of Vornado Realty Trust, used an earnings call on Tuesday to castigate Mayor Zohran Mamdani of New York for his “tax-the-rich” rhetoric, which he likened to a racial slur or a pro-Palestinian rallying cry.

“I must say that I consider the phrase ‘tax the rich’ — quote, tax the rich — when spit out with anger and contempt by politicians both here and across the country, to be just as hateful as some disgusting racial slurs and even the phrase, ‘from the river to the sea,’” Mr. Roth said, referring to the pro-Palestinian phrase that some Jews believe amounts to a call for ethnic cleansing.

Mr. Roth said “tax the rich” suggests that the wealthy are evil and should be made targets, and he criticized the mayor for singling out Kenneth C. Griffin, a fellow tycoon, in his campaign to force rich New Yorkers to pay more to support the city’s programs.

Mr. Roth said Mr. Mamdani’s decision to film a social media video celebrating Gov. Kathy Hochul’s proposed pied-à-terre tax in front of Mr. Griffin’s multistory penthouse — in a building developed by Vornado — was “dangerous” and an “ugly, unnecessary video stunt.”

Mr. Griffin, who bought the penthouse in 2019 for $238 million, had no immediate comment.

Joe Calvello, a spokesman for the mayor, said in a statement that “Mayor Mamdani wants all New Yorkers to succeed,” including Mr. Griffin, “who is a major employer in our city and a powerful figure in our economy.”

He added: “That does not negate the fact, however, that our tax system is fundamentally broken. It rewards extreme wealth while working people are pushed to the brink.”

Mr. Mamdani, 34, ran for office promising to fund expansive new government programs by raising taxes on wealthy individuals and major corporations. Mr. Roth spent heavily against Mr. Mamdani and in favor of his opponent, former Gov. Andrew Cuomo.

But in the face of a budget gap, Mr. Mamdani, a democratic socialist, has instead said those same taxes are also necessary to balance the books.

Unfortunately for Mr. Mamdani, New York City does not control its own tax policy, and Ms. Hochul, who is facing re-election this year, has steadfastly refused to accede to Mr. Mamdani’s demands. But facing pressure from Mr. Mamdani’s base, she did embrace a longstanding proposal to tax expensive second homes in the five boroughs.

And so, on April 15, Tax Day, Mr. Mamdani stood in front of Mr. Griffin’s building and claimed victory.

“This is an annual fee on luxury properties worth more than $5 million, whose owners do not live full-time in the city, like for this penthouse, which hedge fund C.E.O. Ken Griffin bought for $238 million,” Mr. Mamdani said in the video, which has since been viewed 52 million times.

At the time Mr. Griffin bought it, the condo was the most expensive home in America.

Mr. Griffin, who is worth an estimated $50 billion, responded on Tuesday with pique.

“It was creepy and weird,” Mr. Griffin said of Mr. Mamdani’s comments during an onstage interview at an investment conference in Beverly Hills, Calif.

Mr. Griffin elaborated in a separate Tuesday interview on CNBC.

Mr. Mamdani “seems to have forgotten that the C.E.O. of another American company was assassinated just blocks from where I live in New York,” Mr. Griffin said, referring to the 2024 killing of Brian Thompson, the chief executive of UnitedHealthcare.

A week after Mr. Mamdani’s video, Gerald Beeson, the chief operating officer of Citadel, Mr. Griffin’s hedge fund, sent out a letter to his colleagues suggesting that the company might mothball a new $6 billion skyscraper headquarters on Park Avenue that it had been planning to build with Vornado, denouncing Mr. Mamdani’s rhetoric and noting Citadel’s existing contributions to the city.

“Over the past five years, our principals and team members (including nonresidents) have paid nearly $2.3 billion dollars in city and state taxes, providing funds to support the city’s infrastructure, schools, parks and first responders,” Mr. Beeson wrote.

Mr. Griffin said on Tuesday that the development would “probably” move forward, even as he said that Citadel has also decided to expand its office space in Miami, a move for which he also blamed Mr. Mamdani.

“We will add far more jobs in Miami over the next decade as an immediate and direct consequence of the mayor’s poor decision here, with respect to his posting of that video,” Mr. Griffin said.

Mr. Griffin has a history of leaving major American cities in the dust. He famously left Chicago amid rising crime and a feud with Gov. JB Pritzker.

Possibly aware of that, Mr. Mamdani has since softened his rhetoric on Mr. Griffin, even thanking him during a recent Police Department ceremony for funding a memorial wall for fallen officers.

And Mr. Roth on Tuesday offered a note of modest praise for Mr. Mamdani.

“Our mayor is young, smart and energetic,” Mr. Roth said. “With a little tweak here, a little tweak there, his leadership could make this great city even greater.”

But Mr. Griffin deserves an apology, Mr. Roth argued.

“The rich, whom the politicians are targeting, started with nothing, are the epitome of the American dream,” he said. “They are at the top of the great American economic pyramid for a reason. They should be praised and thanked.”

Rob Copeland contributed reporting.