Sen. Mark Kelly (D-Ariz.) on Jan. 12 sued War Secretary Pete Hegseth and other defense officials, alleging they violated the U.S. Constitution when they investigated and punished him for participating in a video encouraging troops to disobey “illegal orders.”

“The video’s message—that service members ‘can refuse illegal orders’—is a plain statement of blackletter law,” the lawsuit from Kelly, a retired Navy captain, stated.

The Trump administration’s response to the video, which included describing its participants as engaging in sedition and launching an investigation, “punish Senator Kelly for his protected speech, according to the suit, which was filed in federal court in the District of Columbia.

Kelly’s statements “are entitled to First Amendment protection because they were neither ‘directed to inciting or producing imminent lawless action’ nor ‘likely to incite or produce such action,’” the legal complaint added, quoting from a previous court ruling.

“We are aware of the litigation,” a Department of War official told The Epoch Times in an email. The official declined further comment.

Hegseth earlier in January said that he was censuring Kelly for “reckless misconduct” over the video, in which Kelly said, “Our laws are clear; you can refuse illegal orders.”

Hegseth said that Kelly’s statements were seditious and violated the Uniform Code of Military Justice, including an article that prohibits conduct unbecoming of an officer.

The department “has initiated retirement grade determination proceedings under 10 U.S. Code, Section 1370(f), with reduction in his retired grade resulting in a corresponding reduction in retired pay,” Hegseth said, citing a federal law.

Kelly was given 30 days to respond, and the retirement determination process will be completed within 45 days, according to the war secretary.

“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 also said at the time.

In the lawsuit, Kelly said that the Constitution’s Speech or Debate Clause covers his activity, and provides absolute immunity. He also said the matter raises concerns that the executive branch can subordinate the legislative branch.

“If permitted to stand, the Secretary’s censure and the grade-determination proceedings that he has directed will inflict immediate and irreparable harm,” the filing said.

“The censure, the grade-reduction process, and its inevitable outcome impose official punishment for protected speech, chill legislative oversight, and threaten reductions in rank and pay. Each of these actions also signals to retired service members and Members of Congress that criticism of the Executive’s use of the armed forces may be met with retaliation through military channels.”