Sen. Kelly sues the Pentagon over attempts to punish him, declaring it unconstitutional

Hegseth said the Jan. 5 censure — by itself simply a formal letter with little practical consequence — was “a necessary process step” to proceedings that could result in a demotion from Kelly’s retired rank of captain and subsequent reduction in retirement pay.

Kelly asked the federal court in Washington, D.C., to rule that the censure letter, the proceedings about his rank and any other punishments against him are “unlawful and unconstitutional."

“The First Amendment forbids the government and its officials from punishing disfavored expression or retaliating against protected speech,” his lawsuit says. “That prohibition applies with particular force to legislators speaking on matters of public policy.”

U.S. District Judge Leon, who was nominated to the bench by Republican President George W. Bush, scheduled a hearing on Thursday in Washington, D.C., for Kelly's request for a temporary restraining order.

The legal action of a sitting U.S. senator suing the defense secretary is rare, if not jarring, and the latest effort from members of Congress to push back against what they see as an out-of-control executive branch.

The censure stemmed from Kelly’s participation in a video in November with five other Democratic lawmakers — all veterans of the armed services and intelligence community — in which they called on troops to uphold the Constitution and not to follow the Trump administration's military directives if they were unlawful.

The 90-second video was first posted on a social media account belonging to Sen. Elissa Slotkin. Reps. Jason Crow, Chris Deluzio, Maggie Goodlander and Chrissy Houlahan also appeared in the video.

Republican President Donald Trump accused the lawmakers of sedition “punishable by DEATH” in a social media post days later.

Kelly and the other lawmakers have not backed down from their video, which was released as the Pentagon began attacking suspected drug-smuggling boats in the waters near Venezuela. The attacks have now killed at least 115 people.

The Pentagon opened an investigation of Kelly in late November, citing a federal law that allows retired service members to be recalled to active duty on orders of the defense secretary for possible court-martial or other punishment.

Although all six lawmakers served in the military or the intelligence community, Hegseth said Kelly was the only one facing investigation because he is the only one who formally retired from the military and still falls under the Pentagon’s jurisdiction.

Hegseth, the Defense Department, Navy Secretary John Phelan and the Navy are named as defendants in the lawsuit. The Pentagon said in a statement it was aware of the lawsuit, but "as a matter of policy, the Department does not comment on ongoing litigation.”

Kelly said in a statement on Monday that he is “standing up for the rights of the very Americans who fought to defend our freedoms.” He accused Hegseth of trying to suppress dissent by threatening military veterans with depriving them of their rank and pay.

“That’s not the way things work in the United States of America, and I won’t stand for it,” Kelly said.

Associated Press writer Ben Finley and Congressional Correspondent Lisa Mascaro contributed to this report.