WASHINGTON – U.S. Sen. Mark Kelly alleged that President Donald Trump is sending a “message” that Americans can't criticize their government − after the Pentagon last week opened an investigation into the Arizona Democrat that could include recalling him to active duty for court-martial proceedings.

“They're trying to send a message to retired service members, to government employees, to members of the military, to elected officials, and to all Americans who are thinking about speaking up, you better keep your mouth shut, or else,” Kelly, a retired U.S. Navy captain, said at a Dec. 1 press conference on Capitol Hill.

The Pentagon announced last week that it was investigating Kelly for "serious allegations of misconduct." The move came after Kelly joined a group of Democratic lawmakers who released a video telling service members they have the right not to obey orders they believe to be illegal.

Trump’s War Department in a post on X last week confirmed it would begin an investigation into Kelly that could “include recall to active duty for court-martial proceedings or administrative measures.” The post cited the Uniform Code of Military Justice, the federal law that outlines the military's criminal code.

However, Kelly at his press conference said the Trump administration's public comments are “the only notification that we have received to date” on a potential court martial. Legal and military experts told USA TODAY that a case against Kelly faces major hurdles and would likely be "dead on arrival" in military courts.

“It's a dangerous moment for the United States of America when the president and his loyalists use every lever of power to silence United States senators for speaking up,” Kelly said.

The FBI last week also requested interviews with the Arizona senator and the five other Democratic members of Congress who participated in the video.

Shortly after the clip was released, Trump in a flurry of social media posts accused the Democratic lawmakers of "SEDITIOUS BEHAVIOR, punishable by DEATH!" He later told Fox News that he does not believe the lawmakers should be executed but warned that they're in "serious trouble."

Addressing Trump’s initial social media posts on the video, Kelly claimed the president has “no regard for the rule of law.” But the senator also said he isn't planning to sue Trump for his public criticism.

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Kelly also criticized recent U.S. strikes on suspected drug boats, following a report that the U.S. military carried out a hit on a vessel in the Caribbean and killed two survivors as they clung to the wreckage.

Congress was briefed on the first three strikes, Kelly said. But the member of the Senate Armed Services Committee alleged officials were “tying themselves in knots, trying to explain why this entire operation is legal.”

He said he wants officials associated with strikes to come before the committee to lay out the legal argument to the American public, including addressing concerns about due process, a guarantee under the 14th Amendment to the Constitution.

The Trump administration is facing increased scrutiny from a bipartisan group of lawmakers following the most recent strikes, though the president's allies have said they're national security efforts.

“If there is anyone who needs to answer questions in public, and under oath, it is Pete Hegseth,” Kelly said.

This article originally appeared on USA TODAY: 'Keep your mouth shut.' Mark Kelly hits back at Trump, Pentagon investigation

Reporting by Rebecca Morin, USA TODAY / USA TODAY

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