Defense Secretary Pete Hegseth could face an impeachment vote in the House as early as this week, as lawmakers return to Washington after an election in which voters delivered a sweeping rebuke of the Trump administration and the president’s handling of the war with Iran.
The effort is being led by Representative Thomas Massie, Republican of Kentucky, who on Monday called up a resolution accusing Mr. Hegseth of violating federal law and the Constitution, and abusing his authority on a number of fronts.
Democrats have signaled broad support for the effort, and several Republicans have expressed discontent with Mr. Hegseth, though the outcome remains uncertain in a narrowly divided House.
Here is what to know about the charges, the process and what could happen next.
The measure charges Mr. Hegseth with violating the Constitution.
Mr. Massie, who lost his primary in May to a challenger backed by President Trump, has introduced eight articles of impeachment against Mr. Hegseth, three of them focused on his conduct of the war with Iran.
The articles accuse the defense secretary of waging war without congressional authorization and continuing the military campaign after Congress voted to direct the president to terminate the conflict or seek authorization to continue it. The resolution also accuses Mr. Hegseth of violating deadlines under the War Powers Resolution, which requires the withdrawal of American forces from unauthorized hostilities after 60 days, with a possible 30-day extension.
The remaining charges accuse Mr. Hegseth of carrying out unlawful military strikes against suspected drug traffickers; unlawfully capturing Venezuela’s president, Nicolás Maduro; conducting unauthorized military operations in Yemen; disregarding laws intended to minimize civilian casualties; and abusing his power by retaliating against Senator Mark Kelly for protected speech.
It is up to Speaker Mike Johnson to decide whether the chamber will vote on each of the eight articles or if they will be considered as a package.
Mr. Hegseth has rejected the allegations, calling the impeachment effort a political sham. He is scheduled to hold a news conference on Tuesday morning to respond to the charges.
“Secretary Hegseth will not back down or be deterred by politicians seeking to score partisan points or launch phony investigations where no wrongdoing exists,” Sean Parnell, the Pentagon spokesman, said in a statement on Monday in which he said Mr. Hegseth intended to serve until the end of President Trump’s term.
Mr. Trump has backed his defense secretary and said he intends to keep Mr. Hegseth in his job.
A majority is required to impeach Mr. Hegseth.
The Constitution lays out the process for Congress to impeach and remove presidents, judges and other federal civil officers, including cabinet secretaries.
The first step is in the House, which considers articles of impeachment alleging treason, bribery or other high crimes and misdemeanors. A simple majority is required to approve any article. Impeachment amounts to a formal accusation by Congress, which is then sent to the Senate for a trial to determine whether the official should be convicted and removed from office.
House rules allow any member to propose impeachment articles and require that the body consider them within two legislative days. Congressional leaders — in this case Republicans — have no power to block a vote, but they can try to head off the impeachment by either moving to send the charges to a committee, delaying final action, or to table them, which would effectively kill the effort.
If the House were to impeach Mr. Hegseth, it would take a two-thirds vote of senators present to convict and remove him.
The outcome of the impeachment vote is uncertain.
Democrats are widely expected to support impeaching Mr. Hegseth, and Representative Hakeem Jeffries, the minority leader, declared on Sunday that he was a “hard yes.” With Republicans holding a razor-thin majority, as few as three Republican defections or a few absences could be enough to put the resolution over the top.
Apart from Mr. Massie, several Republicans have expressed frustration with the secretary without committing to impeachment. Representative French Hill, Republican of Arkansas, said Sunday that he wanted to hear the arguments but cautioned that poor performance alone did not necessarily constitute an impeachable offense.
“I don’t know if we have enough votes,” Mr. Massie told reporters on Monday. “I’m doing this because it’s the right thing to do.”
Beyond the political calculations, many lawmakers are considering whether policy decisions ordered by the president warrant impeachment. When House Republicans impeached Alejandro Mayorkas, who served as the homeland security secretary under President Joseph R. Biden Jr., over his handling of immigration enforcement, Democrats opposed the charges, arguing that policy choices did not constitute impeachable offenses. The Republican-led House impeached Mr. Mayorkas, but the Senate dismissed the charges.
There is no fixed timeline for impeachment.
If the House were to impeach Mr. Hegseth, he would remain defense secretary while the articles were pending, and it would be up to House leaders to decide when to send the matter to the Senate for a trial.
Unlike legislation, however, impeachment resolutions do not die at the end of a Congress, so Democrats, who will control the House and Senate starting Jan. 3, would be able to take up the matter when they assume power.
Eric Schmitt contributed reporting.
