Environmentalists have long faced harassment, imprisonment and other forms of retribution in some parts of the world. The U.S. has largely been an exception, a place where people and organizations can freely and safely pursue efforts to protect human health and nature — sometimes working hand in hand with the government.

But the treatment of people who fight pollution has palpably changed in recent months.

Nonprofit environmental groups are facing attacks from the Trump administration, subpoenas from criminal investigations, online harassment and industry lawsuits they say are designed to intimidate them into silence. In recent weeks, fears have grown that the administration will seek to revoke the nonprofit status of at least some groups.

Today, on Earth Day, ProPublica is publishing an interview with Abigail Dillen, president of Earthjustice, the country’s biggest public interest environmental firm, about the escalating hostility environmentalists face. Over the past five decades, Earthjustice’s lawyers have helped to establish the first federal limits on mercury and other chemicals emitted by power plants, successfully pushed for bans on toxic pesticides and fought to protect hundreds of endangered species.

But the future of the environmental movement is in peril. The shift has been led in no small part by the Environmental Protection Agency, which is tasked with protecting the public’s air and water. President Donald Trump’s head of the EPA, Lee Zeldin, has defunded and sharply criticized some environmental organizations. For eight nonprofit groups that received $20 billion in federal money aimed at promoting clean energy, Zeldin has gone further, working with the FBI on a criminal investigation into the Greenhouse Gas Reduction Fund, the grant program that funds them.