Last Thursday afternoon, as the work week was winding down before the July 4th holiday, 139 employees of the Environmental Protection Agency received an unwelcome email. They were being put on administrative leave with pay for the next two weeks, pending the outcome of an investigation.

Five of those suspended employees were in the EPA’s Region 1 office in Boston, which oversees all of New England.

Their alleged offense was a decision to sign their names to a letter of protest to EPA Administrator Lee Zeldin, expressing their “dissent against the current administration’s focus on harmful deregulation, mischaracterization of previous EPA actions, and disregard for scientific expertise.”

EPA employees who signed the letter say they knew the Trump administration was unlikely to welcome constructive criticism, but news of their suspension still came as a shock.

“I then received a call a little bit later from a representative in HR basically saying that they were investigating the circumstances surrounding my signature on a petition,” one EPA employee in the Boston office told GBH News on the condition that they not be identified. “And specifically, they would be looking to see if I used agency time or resources to sign the letter. I asked the HR rep if I didn’t use agency time and resources, would that mean I would be fine? They said that they could not answer that.”

In all, 620 people signed the letter, including some who had already taken buyout offers and others who were already on administrative leave because their work focused on environmental justice-related projects that the administration has put on hold. It also included some former and current EPA employees who chose to sign anonymously.

“I chose to use my name for that because it’s something I believed in and I do want to look back at this time and be able to say that I stood up for something,” the Boston-office employee told GBH News. “I took this job for a reason. I want to protect the environment, protect public health, and I don’t think that that’s necessarily happening right now with the rhetoric coming from the current administration. So I chose to sign it.”

A spokesperson for the EPA responded to an inquiry from GBH News with a written statement.

“The Environmental Protection Agency has a zero-tolerance policy for career bureaucrats unlawfully undermining, sabotaging, and undercutting the administration’s agenda as voted for by the great people of this country last November,” the statement said, in its entirety.

The agency did not place union representatives who signed the letter on administrative leave.

“Our union is working with our allies to ensure that if discipline comes out of this ... at the end of this investigation period, that we are able to fully represent everyone who spoke out and allow them to exercise their rights to due process,” said Undine Kipka, a union steward of AFGE Local 3428 who signed the letter and also works in the Boston office.

“Hopefully, we’ll ultimately win at the end of the day, because, you know, we think [signing the letter] is completely appropriate,” Kipka said. “And we’re standing up for the mission of the agency, as opposed to diminishing it. We’re standing up for the public, instead of hiding truths from them.”

The letter details “five primary concerns”, including the assertions that misinformation from EPA’s leadership has undermined public trust in the agency, that EPA is ignoring scientific consensus to benefit polluters, and that environmental progress has been reversed in the most vulnerable communities.

“Given the mission of our agency and our responsibility to the public in swearing an oath to the Constitution as public servants, we felt that characterizing, for example, coal as a fuel source, as 'beautiful and clean,' was essentially contradicting our mission at the agency, in the sense that this is a fuel source that is known to emit more pollutants than other types of fuels and causes harm to public health,” Kipka said. “It’s switching back to a dirtier fuel source that emits more greenhouse gasses when it’s burned. That contradicts the idea that we as a country need to take climate change and action towards mitigating the effects of climate change and really addressing it seriously as a crisis.”

Any retaliatory action against employees could amount to a violation of their First Amendment rights, said David Cash, who served as EPA Region 1 Administrator in the Biden administration.

“They have every right to talk about all range of things when they’re outside of their duties, which is what this was,” Cash said. “This letter was written outside their scope of duties. And this is yet another example of this administration adding layers of autocratic actions on to the everyday business that they’re doing.”

Many of those who signed the letter have served under both Democratic and Republican administrations, Cash said.

“But we’ve seen a level of lawlessness and abandonment of core principles of the EPA, like a diminishment of its science capacity and rolling back whole swaths of regulations, and freezing funds that were duly allocated and obligated by Congress,” he said. “And I think these staff members were quite brave to put their names and their careers on the line to protest this abandonment of a long-standing, decades-long bipartisan protection of human health and the environment.”

Part of the beauty of this country, Cash said, is that dissent is tolerated.

“Not only is it tolerated, it should be part and parcel with how we do our business,” he said. “And so this flies in the face of long-standing philosophy of what makes this country great … Administrator Zeldin has every right to not agree with what these staff members are raising, but retaliation against them goes against their First Amendment rights.”

The EPA employee who spoke with GBH News on the condition of anonymity said if what HR told them about the limited scope of the investigation is true, there shouldn’t be any retaliation.

Even so, they said they’re nervous.

“I mean, this administration hasn’t been known to do things by the book,” the employee said. “So anything is possible. I definitely recognize that, and I am worried about it, but I wouldn’t change what I did. And we’ll face what comes, and I’ll keep fighting for what I think is right, regardless of what happens.”