The Trump administration, which has systematically rolled back firearms regulations since returning to office, has also gutted federal gun violence prevention efforts, slashing funding for programs and research and even suppressing taxpayer-funded reports aimed at reducing gun injuries and deaths.

The cutbacks, which span agencies throughout the federal government, represent a shift in philosophy about how to address gun violence, away from a public-health-oriented approach focused on prevention, to a law-and-order approach focused on beefing up police departments and seizing illegal weapons. The move away from prevention and regulation aimed at saving lives is playing out in other areas of public health too, including illegal drugs and smoking.

The administration’s approach to gun violence also reflects President Trump’s long political alliance with gun rights groups and his determination to undo the policies of his predecessor, former President Joseph R. Biden Jr. Soon after taking office, Mr. Trump shuttered Mr. Biden’s White House Office of Gun Violence Prevention, ordered a review of Mr. Biden’s firearms policies and issued an executive order titled, “Protecting Second Amendment Rights.”

The Justice Department’s civil rights division also took the highly unusual step last week of suing Virginia and California to overturn those states’ restrictions on gun ownership. The suit was the division’s “first ever affirmative litigation in favor of expanding gun rights,” said Joseph Blocher, an expert on Second Amendment law at Duke University.

Still, the cuts are perplexing to people involved in prevention work because Mr. Trump is no stranger to gun violence. He has survived three assassination attempts, and his close ally Charlie Kirk was gunned down while giving a speech last year. Mr. Kirk’s accused assassin faces a court hearing in Utah this week. The man accused of trying to kill Mr. Trump at a press gala in April appeared in federal court in Washington last week.

“It is a grand irony,” said Amy Solomon, who oversaw a violence prevention program at the Justice Department when she served as assistant attorney general in the Biden administration. That program, the Community Based Violence Intervention and Prevention Initiative, has since lost $150 million in funding, which was steered to law enforcement, she said.

“The groups and organizations who work on this are very strong and very resilient, but so many of them have had to cut services, have had to lay off staff; some of them have closed their doors altogether,” Ms. Solomon said. “And what’s replacing it is a very heavy-handed, law-enforcement-centric focus that frankly isn’t even focusing on the violence.”

Spokespeople for the White House and the Departments of Justice, Homeland Security and Health and Human Services said the administration’s policies have made Americans safer while eliminating wasteful spending.

“The Trump administration remains totally committed to being responsible stewards of American taxpayer dollars, and that includes no longer funding programs that were wasteful, misdirected and counterproductive,” said Abigail Jackson, a White House spokeswoman.

Ms. Jackson and her colleagues at other agencies also credited the president with a marked decline in violent crime in 2025. They cited an analysis of 40 cities by the nonprofit Council on Criminal Justice, which found a steep drop in the murder rate and that violent crime overall had dropped to below its rate in 2019, before the coronavirus pandemic.

But violent crime was also declining under Mr. Biden. Fatimah Loren Dreier is the executive director of the Health Alliance for Violence Intervention, which supports hospital-based violence prevention programs and laid off 20 percent of its staff after the Justice Department funding was cut. She cited recent research showing that the programs, based in trauma centers, can successfully prevent victims of violent injuries, including gunshot wounds, from being injured again.

The programs focus on “retaliatory violence,” she said, which is concentrated in cities with high crime rates. Grounded in the idea that simply stitching up a patient’s wounds will not prevent future violence, they employ doctors, social service workers and “trusted messengers” to follow and counsel patients at risk of being injured again.

“For some cities, there have been historic declines — cities like Baltimore, Chicago,” she said, adding, “It’s pretty remarkable, the impact of these investments.”

At the Department of Homeland Security, the Center for Prevention Programs and Partnerships, aimed at preventing terrorist attacks and “targeted violence,” lost $18.5 million last year. Bill Braniff, the counterterrorism expert who founded it, left government for academic work.

The center awarded its last grants in September 2024, according to its website. In announcing the grant terminations, the Trump administration called it a “cash cow for radical activists” and spotlighted a handful of groups, including some focused on violence against gay, lesbian, bisexual and transgender people.

The program also funded groups at Auburn University in Alabama, the Nevada university system, a Minnesota sheriff’s office, an educational nonprofit in western Kentucky, the Jewish Federation of Pittsburgh and Louisiana’s largest historically Black college. Those programs were largely designed to help local officials identify and combat threats.

Mr. Braniff, who is an expert on global jihadist ideology, said the center was based in part on the Centers for Disease Control and Prevention’s violence prevention work. He had concluded that the post-9/11 approach of “killing and capturing folks” was not enough, he said, and too focused on the Muslim community. He hoped to broaden the center’s reach.

“One of the virtues of the public-health-informed approach,” he said, “is that it allows us to think about shared risk and protective factors for violence, and start to think about interventions that weren’t indexed on ideology.”

After The New York Times inquired about Mr. Trump’s policies, the Bureau of Alcohol, Tobacco, Firearms and Explosives issued a news release saying its “shift in priorities” has resulted in nearly 50,000 firearms “seized from criminals” since January 2025.

But a majority of gun-related deaths in the United States, roughly 60 percent, are suicides, and experts say beefing up policing may not prevent them. Roughly 44,000 Americans, an average of 120 a day, died from gun-related injuries, including accidents and suicides, each day in 2024, the most recent year for which figures are available.

Over the past four decades, public health experts have coalesced around the idea that gun violence, like infectious disease, can be tracked, studied and prevented. But federally funded gun violence prevention ran into trouble on Capitol Hill in 1996, when Republicans in Congress effectively put an end to C.D.C.-funded research.

The research resumed with bipartisan support in 2021. But beyond fulfilling grant obligations that date to the Biden administration, the Trump administration has not funded new research. In 2024, the Biden administration announced $12.9 million in new funding for gun violence prevention research, but none of those grants have been awarded.

Health Secretary Robert F. Kennedy Jr., whose father and uncle were assassinated, has said he does not view gun violence as a public health problem. “I would say it’s an epidemic,” Mr. Kennedy said at a House hearing in April. “I think it’s a law enforcement issue and not public health.”

Mr. Kennedy has presided over layoffs that have gutted the C.D.C.’s Division of Violence Prevention. But last week, a day after The Times sought comment for this article, the administration posted two notices alerting researchers to the C.D.C.’s plans for future violence prevention studies, though the notices do not mention firearms.

Sarah DeGue, who spent 17 years in the division, focused primarily on sexual and intimate partner violence, was among those who were laid off. She now works as a consultant, she said, and donates her time to communities in need.

Although the division is hobbled, it is still tracking and reporting gun injuries and deaths, she said.

“It’s great that the data is still there,” Dr. DeGue said. “But what they’re missing is being able to do anything about the data. They don’t have the capacity anymore. They don’t have the staff to do any research, to develop any strategies or to help states and communities actually implement what works.”

Apart from declining to fund new research, the administration has also suppressed previous studies and reports.

After Congress passed a bipartisan gun safety bill in 2022 that contained funding to help states enact so-called red flag laws, the Department of Health and Human Services commissioned a report on the statutes. The laws authorize courts to issue “extreme risk protection orders,” or ERPOs, allowing law enforcement to temporarily remove firearms from people deemed dangerous by a judge. Mr. Trump briefly embraced red flag laws, which the gun lobby fiercely opposes, during his first administration, in the aftermath of a mass shooting in 2019.

The report, financed by the Substance Abuse and Mental Health Services Administration, explored the scientific evidence behind the laws, and offered a guide to help state mental health authorities enforce them. It was posted on the agency’s website at the tail end of the Biden administration but vanished after Mr. Trump took office.

The administration also took down an advisory issued by the surgeon general declaring firearm violence a public health crisis. While that made headlines, the removal of the “ERPO report,” as its authors call it, attracted no notice.

The document has survived on a website hosted by the nonprofit Ad Council, though it is difficult to find. The report’s lead author, Jeffrey W. Swanson, an expert in mental health and gun violence at Duke University whose research shows that red flag laws save lives, said he had no idea it survived online, and that he had been given no explanation for its removal.

“The American people paid for the ERPO report,” Dr. Swanson said, adding that he was speaking for himself, not his university. “They deserve to see it, and they deserve a public health system where scientific knowledge is not dependent upon political convenience.”

A spokeswoman for Mr. Kennedy, Emily Hilliard, did not respond directly to questions about what happened to the reports, but said federal health officials “continue to comply” with the president’s executive order on protecting Second Amendment rights, “while supporting firearm injury prevention.”

Lawrence O. Gostin, a public health law expert at Georgetown University, said the Trump administration may have violated the Paperwork Reduction Act, which governs how federal agencies disseminate public information. And he said taking down a surgeon general’s advisory amounted to “a gross violation” of Mr. Kennedy’s public duty.

“Removing these reports from public view,” Mr. Gostin said, “is the purest form of political control over public health and scientific integrity.”