WASHINGTON — More than 20 civil service employees resigned Tuesday from billionaire Trump adviser Elon Musk’s Department of Government Efficiency, saying they were refusing to use their technical expertise to “dismantle critical public services.”

“We swore to serve the American people and uphold our oath to the Constitution across presidential administrations,” the 21 staffers wrote in a joint resignation letter, a copy of which was obtained by The Associated Press. “However, it has become clear that we can no longer honor those commitments.”

The employees also warned that many of those enlisted by Musk to help him slash the size of the federal government under President Donald Trump’s administration were political ideologues who did not have the necessary skills or experience for the task ahead of them.

The mass resignation of engineers, data scientists, designers and product managers is a temporary setback for Musk and the Republican president’s tech-driven purge of the federal workforce. It comes amid a flurry of court challenges that have sought to stall, stop or unwind their efforts to fire or coerce thousands of government workers out of jobs.

In a statement, White House press secretary Karoline Leavitt was dismissive of the mass resignation.

“Anyone who thinks protests, lawsuits, and lawfare will deter President Trump must have been sleeping under a rock for the past several years,” Leavitt said. “President Trump will not be deterred from delivering on the promises he made to make our federal government more efficient and more accountable to the hardworking American taxpayers.”

Musk posted on his social media site X that the staffers were “Dem political holdovers” who “would have been fired” had they not resigned.

The staffers who resigned had worked for what was once known as the United States Digital Service, but said their duties were being integrated into DOGE.

Their former office, the USDS, was established under President Barack Obama after the botched rollout of Healthcare.gov, the web portal that millions of Americans use to sign up for insurance plans through the Democrat’s signature health care law.

All previously held senior roles at such tech companies as Google and Amazon and wrote in their resignation letter that they joined the government out of a sense of duty to public service.

Trump’s empowerment of Musk upended that. The day after Trump’s inauguration, the staffers wrote, they were called into a series of interviews that foreshadowed the secretive and disruptive work of DOGE.

According to the staffers, people wearing White House visitors’ badges, some of whom would not give their names, grilled the nonpartisan employees about their qualifications and politics. Some made statements that indicated they had a limited technical understanding. Many were young and seemed guided by ideology and fandom of Musk — not improving government technology.

Earlier this month, about 40 staffers in the office were laid off. The firings dealt a devastating blow to the government’s ability to administer and safeguard its own technological footprint, they wrote.

Roughly one-third of the 65 staffers who remained at USDS quit Tuesday.

“We will not use our skills as technologists to compromise core government systems, jeopardize Americans’ sensitive data, or dismantle critical public services,” they wrote. “We will not lend our expertise to carry out or legitimize DOGE’s actions.”

The slash-and-burn effort Musk is leading diverges from what was initially outlined by Trump during the 2024 presidential campaign. DOGE, a nod to Musk’s favorite cryptocurrency meme coin, was initially presented as a blue-ribbon commission that would exist outside government.

After the election, however, Musk hinted there was more to come, posting to X, “Threat to democracy? Nope, threat to BUREAUCRACY!!!”

Still, Musk has tried to keep technical talent in place, with the bulk of the layoffs in the Digital Service office focused on people in roles like designers, product managers, human resources and contracting staff, according to interviews with current and former staff.

Of the 40 people let go earlier this month, only one was an engineer — an outspoken and politically active staffer name Jonathan Kamens, who said in an interview with the AP that he believes he was fired for publicly endorsing Vice President Kamala Harris, a Democrat, on his personal blog and being critical of Musk in chats with colleagues.