Defense Secretary Pete Hegseth has approved sending up to 600 military lawyers to the Justice Department to serve as temporary immigration judges, according to a memo reviewed by The Associated Press.

The military will begin sending groups of 150 attorneys — both military and civilians — to the Justice Department “as soon as practicable,” and the military services should have the first round of people identified by next week, according to the Aug. 27 memo.

The effort comes as the Trump administration more regularly turns to the military as it cracks down on illegal immigration through ramped-up arrests and deportations. Its growing role in the push includes troops patrolling the U.S.-Mexico border, National Guard members being sent into U.S. cities to support immigration enforcement efforts, housing people awaiting deportation on military bases and using military aircraft to carry out deportations.

The administration’s focus on illegal immigration has added strain to the immigration courts, which were already dealing with a massive backlog of roughly 3.5 million cases that has ballooned in recent years. An organization for immigration lawyers called the new directive a “destructive” move meant to undermine the courts.

At the same time, more than 100 immigration judges have been fired or left voluntarily after taking deferred resignations offered by the Trump administration, their union says. In the most recent round of terminations, the International Federation of Professional and Technical Engineers said in July that at least 17 immigration judges had been fired “without cause” in courts across the country.

That has left about 600 immigration judges, union figures show, meaning the Pentagon move would double their ranks.

The Justice Department, which oversees the immigration courts, requested the assistance from the Defense Department, according to the memo sent by the Pentagon’s executive secretary to his DOJ counterpart. The military lawyers’ duties as immigration judges will initially last no more than 179 days but can be renewed, it said.

A DOJ spokesperson referred questions about the plan to the Defense Department, where officials directed questions to the White House.

A White House official said Tuesday that the administration is looking at a variety of options to help resolve the significant backlog of immigration cases, including hiring additional immigration judges. The official, who was not authorized to comment publicly and spoke on condition of anonymity, said the matter should be “a priority that everyone — including those waiting for adjudication — can rally around.”

The head of the American Immigration Lawyers Association decried bringing in temporary judges who lack expertise in immigration law, saying “it makes as much as sense as having a cardiologist do a hip replacement.”

“Expecting fair decisions from judges unfamiliar with the law is absurd. This reckless move guts due process and further undermines the integrity of our immigration court system,” said Ben Johnson, the organization’s executive director.

The memo stressed that the additional attorneys are contingent on availability and that mobilizing reserve officers may be necessary. Plus, the document said DOJ would be responsible for ensuring that anyone sent from the Pentagon does not violate the federal prohibition on using the military as domestic law enforcement, known as the Posse Comitatus Act.

The administration faced a setback on its efforts to use troops in unique ways to combat illegal immigration and crime, with a court ruling Tuesday that it “willfully” violated federal law by sending National Guard troops to Los Angeles in early June.

It is not immediately clear what impact shifting that number of military attorneys would have on the armed forces’ justice system. The attorneys, called judge advocates, have a range of duties much like civilian lawyers, from carrying out prosecutions, acting as a defense attorney or offering legal advice.