Defense Secretary Pete Hegseth has suspended or placed under investigation at least eight service members over celebrating the assassination of conservative leader Charlie Kirk.

At least one legal expert says Hegseth's campaign goes "beyond the pale" and is chilling free expression among members of the military.

Task & Purpose reported last week that the disciplinary actions include the suspension of at least five Army officers and an Air Force senior master sergeant, along with a Marine officer who was relieved of his recruiting duties and placed under investigation, and an Army Reserve major who is also under investigation.

They reportedly follow an order from Hegseth to identify anyone working for the Pentagon who cheered Kirk's killing earlier this month.

Former Air Force Judge Advocate and Southwestern Law School professor Rachel VanLandingham told The Hill that it's "extremely dangerous" for the Trump administration to mount a "witch hunt" for those criticizing Kirk, as it threatens the historically nonpartisan nature of the military.

"Going beyond things that directly impact good order and discipline, directly impact the military mission, just to retribute and punish and therefore suppress and chill any personal expression based on ideological grounds is beyond the pale," VanLandingham, a retired Air Force lieutenant colonel, said.

"We've never seen institutionally ... the ability of the Pentagon to limit speech utilized to such an extent purely on ideological grounds," she added.

Kirk, who was the co-founder of the conservative youth group Turning Point USA, was gunned down while speaking on the first stop of his "American Comeback Tour" at Utah Valley University in Orem on Sept. 10. He was 31.

The next day, Hegseth said Pentagon officials were monitoring the social media posts of military members for negative comments about the slain conservative activist.

"We are tracking all these very closely — and will address, immediately," Hegseth wrote on X. "Completely unacceptable."

He was responding to a post by Pentagon spokesman Sean Parnell, who wrote, "It is unacceptable for military personnel and Department of War civilians to celebrate or mock the assassination of a fellow American."

Four days after Kirk's death, Parnell said those who openly denigrate Kirk or mocked his murder were in violation of their oath of office, had acted in a manner unbecoming to a service member, and had betrayed "the Americans they've sworn to protect & dangerously incompatible with military service."

Some of the larger conservative social media accounts and many smaller ones focused on the military have flagged individual posts that negatively commented on Kirk's killing, drawing attention to them by tagging Hegseth and other senior Pentagon officials.

Hegseth's push for repercussions has been panned by those on the left, including Rep. Jason Crow, D-Colo., a former Army Ranger.

"@PeteHegseth hunting down and prosecuting service members for their individual political beliefs is dangerous and un-American," Crow posted on X. "We must condemn political violence AND allow peaceful speech that doesn't impact the chain of command."

Across the aisle, Rep. Ryan Zinke, R-Mont., a retired Navy SEAL, said Wednesday that he welcomed the removal of such service members.

"Look, if you're celebrating the loss of life, a political assassination of a father, a husband, if you're celebrating a political assassination, I can tell you, I don't want you on my SEAL team," Zinke told "CNN This Morning."

"I don't want you in my Department of Defense or Department of War," he continued. "I don't want you, a sailor, a soldier, a Marine, if you're celebrating that."

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