Sen. Mark Kelly is suing Defense Secretary Pete Hegseth and other senior military leaders over the Pentagon’s attempt to punish him for telling troops not to follow illegal orders.
The Arizona Democrat, in filings made public Monday, asked a federal court to block a review that could demote the former Navy captain’s rank and reduce his retirement pay. Hegseth announced the review this month and censured Kelly for his comments against the administration.
The lawsuit is the latest salvo in a fight that began in November after Kelly and five other Democrats with national security backgrounds released a video reminding troops of their duty not to follow illegal orders. President Donald Trump and Hegseth have attacked their remarks as “seditious.”
The suit names Hegseth as a defendant along with Navy Secretary John Phelan, the Defense Department and the Navy. Kelly served for 25 years in the military, including time as a NASA astronaut and a fighter pilot who flew missions in Operation Desert Storm.
Kelly said in a statement that the lawsuit is necessary to stand up to improper and baseless behavior by Hegseth.
“His unconstitutional crusade against me sends a chilling message to every retired member of the military: if you speak out and say something that the president or secretary of Defense doesn’t like, you will be censured, threatened with demotion, or even prosecuted,” he said. “That’s not the way things work in the United States of America, and I won’t stand for it.”
The Pentagon didn’t immediately respond to a request for comment.
While Kelly and the other lawmakers did not specify in the video what orders they considered illegal, Democrats in recent weeks have argued Trump is putting the military in a legal gray area with deadly strikes against suspect drug smuggling boats in Latin America, the capture and arrest of Venezuelan leader Nicolás Maduro and by deploying the National Guard to U.S. cities.
The Pentagon announced an investigation into Kelly in November for “serious allegations of misconduct” that could result in recalling him to active duty for a court martial. The department last week stopped short of that, with Hegseth announcing proceedings to demote Kelly to a lower rank and reduce his retirement pay.
Kelly’s lawyers argue in the filing that the attacks from Hegseth “violate numerous constitutional guarantees and have no basis in statute” and “should proceed no further.”
Kelly contends Hegseth and Trump’s attacks on him pointed toward a preordained outcome that deprived him of a legitimate opportunity to rebut the allegations against him.
“If permitted to stand, the Secretary’s censure and the grade-determination proceedings that he has directed will inflict immediate and irreparable harm,” his lawyers wrote. “The Constitution does not permit the government to announce the verdict in advance and then subject Senator Kelly or anyone else to a nominal process designed only to fulfill it.”
Kelly said he’s being targeted over commentary on issues that are central to his role as a lawmaker: the management of the military by Hegseth, legislation related to war crimes and the military justice system.
The lawsuit argues that punishment for his comments would violate protections — codified in the Constitution’s speech or debate clause — meant to insulate Congress from executive branch pressure.
Kelly and his lawyers also note that “a sitting Member of Congress has never been subject to military punishment based solely on his speech.”
