President Donald Trump has purged dozens of judges as part of his sweeping changes to immigration policy.

Since Trump returned to office in January, 139 immigration judges have been fired, taken an early-out offer or been involuntarily transferred, according to the National Association of Immigration Judges — with 24 dismissed last month alone, reported CNN.

“The dismissal of more immigration judges is an illogical and costly setback for the nation’s immigration courts,” said International Federation of Professional & Technical Engineers President Matt Biggs in a statement. “At a time when the backlog has reached historic levels and the administration has made immigration enforcement a central issue, the removal of experienced judges is hypocritical, undermines the law, wastes taxpayer dollars, and further delays justice for citizens and immigrants alike.”

Immigration courts are overseen by the executive branch within the Justice Department, unlike federal courts, so the administration does have tremendous influence over the system. But experts say Trump's purge is like nothing they've seen before.

“You cannot look at this in a vacuum," said Ashley Tabaddor, who served as an immigration judge for 15 years. "This is part and parcel of a very, very grand scheme of creating a very frictionless deportation machine."

Trump's appointees at DOJ started the removals at the beginning of his presidency by abruptly removing senior leadership at the Executive Office for Immigration Review, which oversees the nation’s immigration courts. At least 30 of the judges dismissed had granted more than 30 percent of asylum claims that came before them.

“I believe the Trump administration can’t stand people who play by the rules,” said Shira Levine, who was dismissed after four years as an immigration judge. “My concerns are for the rule of law in this country. In terms of my own personal circumstances, I walked out of that courtroom with great pride, knowing I had done my very best to uphold rule of law and provide fair and full hearings.”

Chloe Dillon told CNN she was abruptly terminated in August by email during the middle of hearing a case.

“The immigration courts are being dismantled," Dillon said. "They are firing judges at an extremely rapid pace. I think it’s fair to say that every judge sitting on a bench thinks they may be or likely will be fired.”

The Justice Department eliminated some requirements for temporary immigration judges to allow any attorney to serve in the role, and the administration has tried to enlist military lawyers, but former immigration judges are concerned they won't have proper training.

“Immigration law is complex,” said a former senior military lawyer. “Yes, I think every judge advocate in the JAG corps could figure it out, because it’s got amazing people, but they all have day jobs too.”