Defense Secretary Pete Hegseth announced Monday that he censured Democratic Sen. Mark Kelly of Arizona, initiating proceedings that could result in a demotion from Kelly’s retired rank of Navy captain and a reduction in his retirement pay.

The censure, a formal letter that Hegseth described as “a necessary process step,” follows Kelly’s participation in a November video in which six Democratic lawmakers — all veterans of the military or intelligence community — called on U.S. service members to uphold the Constitution and defy “illegal orders.”

Investigating and seeking to punish a sitting U.S. senator over statements made in office represents a departure from the Pentagon’s historically apolitical posture. Legal experts say the case raises unresolved constitutional questions — including the scope of the speech or debate clause and whether post-retirement conduct can be the basis for a retirement grade determination — that would likely require resolution in federal court.

The video

The 90-second video was first posted from Sen. Elissa Slotkin’s X account in November. In it, Slotkin, Kelly, and Reps. Jason Crow, Chris Deluzio, Maggie Goodlander, and Chrissy Houlahan spoke directly to service members, with Slotkin acknowledging they were “under enormous stress and pressure right now.” The lawmakers did not reference specific circumstances.

Their message was released amid military operations against boats accused of smuggling drugs in the Caribbean Sea and the eastern Pacific Ocean and President Donald Trump’s attempts to deploy National Guard troops to American cities.

Trump accused the six lawmakers of sedition “punishable by DEATH” in a social media post days after the video appeared.

Investigation and charges

The Pentagon announced an investigation of Kelly in late November, citing a federal law that allows retired service members to be recalled to active duty on the defense secretary’s orders for possible court-martial or other measures. Hegseth previously said Kelly was the only one of the six lawmakers under investigation because he is the only one who formally retired from the military and remains under the Pentagon’s jurisdiction.

In a social media post Monday, Hegseth charged that Kelly’s remarks in the video and afterward violated Uniform Code of Military Justice provisions against conduct unbecoming an officer and violating good order and discipline.

“Captain Kelly’s status as a sitting United States Senator does not exempt him from accountability, and further violations could result in further action,” Hegseth said.

According to Hegseth, Kelly has 30 days to submit a response to the proceedings that will determine whether he is demoted. A decision will be made within 45 days.

Todd Huntley, a retired Navy captain and judge advocate general, described the situation as “novel” and said it raises significant legal questions.

One issue, Huntley said, is whether Kelly’s statements fall under the constitutional protections of the speech or debate clause, which is intended to protect members of Congress from questioning about official legislative acts. A 1968 Supreme Court decision said the provision’s intent was “to prevent legislative intimidation by and accountability to the other branches of government.”

“You can’t punish him for making statements that are consistent with the office he is holding,” said Colby Vokey, a civilian military lawyer and former military prosecutor, citing the constitutional clause.

Huntley also questioned whether the type of proceeding Hegseth is using — known as a retirement grade determination — can apply to conduct that occurred entirely after a service member left active duty. “As far as I know, they’ve always been based on conduct during the individual’s active duty service, even if it only came to light after retirement,” Huntley said. “So, I don’t know if conduct totally after retirement would fit the requirement for such a determination.”

Vokey expressed skepticism about the standard for reducing a retired officer’s rank and pay. “I have no idea what the good cause would be. I think that’s pretty questionable,” he said. Vokey said a lawsuit in federal court would likely be the more effective course of action for Kelly. Huntley noted that Kelly will also have options to appeal any finding within the military.

Kelly’s response

In a lengthy social media post, Kelly said he “never expected” what he described as an “attack” from Trump and Hegseth, recounting his 25 years of Navy service as well as combat and space missions. He called the move “outrageous” and “un-American” and said he would fight the censure “with everything I’ve got — not for myself, but to send a message back that Pete Hegseth and Donald Trump don’t get to decide what Americans in this country get to say about their government.”

Kelly said last month that the investigation was intended to discourage dissent. “This is just about sending a message to retired service members, active duty service members, government employees — do not speak out against this president or there will be consequences,” he said.