Irate Republican lawmakers finally got to chastise Defense Secretary Lloyd J. Austin III face to face on Thursday, chiding him repeatedly for his failure last month to tell his boss that he was in the hospital.
In not notifying President Biden or his own staff that he had prostate cancer that required surgery, and then remaining quiet for three days after developing complications that sent him back to the hospital, Mr. Austin demonstrated a lapse in judgment that breached the chain of command and imperiled national security, the G.O.P. lawmakers said.
The formal title of the House Armed Services Committee hearing struck an ominous tone: “A Review of Defense Secretary Austin’s Unannounced Absence.”
If bartenders and truck drivers have to tell their bosses when they miss work, why shouldn’t the man who is sixth in the line of presidential succession, scolded Representative Mike Waltz, Republican of Florida. “This is about judgment, and poor judgment,” he said.
Mr. Austin deflected most of the questions about accountability with his often repeated mea culpa, apologizing — again — for keeping his hospitalizations at Walter Reed National Military Medical Center in December and January a secret.
“We did have a breakdown in notifications during my January stay at Walter Reed — that is, sharing my location and why I was there,” he told the packed hearing room. “And back in December, I should have promptly informed the president, my team, and Congress and the American people of my cancer diagnosis and subsequent treatment.”
He added, “I take full responsibility.”
On Monday, the Pentagon released an unclassified version of a review of how Defense Department officials, including Mr. Austin, handled his hospitalization. The document offered little if any criticism and faulted no one for the failure to disclose his illness.
Even before the two-hour hearing began, lawmakers had been steaming. Representative Mike D. Rogers, Republican of Alabama and the chairman of the Armed Services Committee, resorted to capital letters to make his point on social media that “the review of Sec Austin’s actions, conducted by his own subordinates & subject to his approval, HELD NO ONE ACCOUNTABLE.”
In his opening statement on Thursday, Mr. Rogers said the chain of command “doesn’t work” when the president does not know whom to call.
“It’s totally unacceptable that it took three days to inform the president of the United States that the secretary of defense was in the hospital, and not in control of the Pentagon,” Mr. Rogers said as he opened the hearing. “Wars were raging in Ukraine and Israel, our ships were under fire in the Red Sea, and our bases were bracing for attack in Syria and Iraq. But the commander in chief did not know that his secretary of defense was out of action.”
Mr. Rogers added: “Someone needs to be held accountable.”
On the other side of the Capitol, senators from both parties voiced frustration after receiving a classified briefing on the Pentagon’s review on Tuesday.
“I have very strong, severe questions remaining for the Pentagon as to how this seeming concealment was handled, and I think there ought to be some public accountability,” Senator Richard Blumenthal, Democrat of Connecticut, told reporters.
Senator Roger Wicker of Mississippi, the senior Republican on the Armed Services Committee, said in a statement, “I remain concerned that the department has yet to account for its failure to comply with federal law and notify Congress or the White House that the secretary was incapacitated.”
Mr. Wicker added, “It is clear that many members of the committee left the briefing frustrated by questions that went unanswered.”
But while Democrats have criticized Mr. Austin, they also tried to emphasize on Thursday that at the end of the day, he did transfer authority to Deputy Defense Secretary Kathleen H. Hicks, even if she did not know why.
Representative Adam Smith, Democrat of Washington, along with several other Democrats on the committee, used the hearing to press Republicans to pass a Ukraine aid package.
“If we care about confronting our adversaries, rather than nit-picking the secretary of defense about his precise process in the situation, we should go ahead and pass” the Ukraine aid bill, he said. “I would challenge any member on the other side of this aisle to claim that the secretary of defense not fully informing the president for three days is somehow more important than walking away from that obligation that we have made and that the whole world is watching us on.”
In fact, despite the bipartisan annoyance at Mr. Austin’s secrecy, it took only minutes for the hearing to assume the usual characteristics of partisan squabbling in Washington.
“Is it typical that the president will go three days without talking to the secretary of defense?” asked Representative Jim Banks, Republican of Indiana. “Either the president is that aloof or you are irrelevant.”
Representative Elise Stefanik, Republican of New York, added, “What disciplinary action would a junior service member face if he or she failed to properly notify their chain of command and failed to report for duty?”
Mr. Austin, who still is moving slowly and with care, replied, “I think the chain of command would be concerned about why they were in a hospital, and it makes sure that they’re doing the right things to take care of them and their family.”
Mr. Austin underwent an elective medical procedure at Walter Reed on Dec. 22. He did not tell the White House or senior administration officials that he was having surgery for a diagnosis he would later describe as a “gut punch.”
He was released before Christmas but returned on New Year’s Day with complications that kept him in the intensive care unit for two weeks.
Mr. Austin’s chief of staff, Kelly Magsamen, did not inform the White House that her boss was in the hospital until three days later. The extraordinary breach of protocol — Mr. Austin is in charge of the country’s 1.4 million active-duty service members at a time when wars in Gaza and Ukraine dominate the American national security landscape — baffled officials across the government, including at the Pentagon.
Mr. Austin tried to explain himself in early February when he told reporters at the Pentagon that “I did not handle this right.”
“I should have told the president about my cancer diagnosis,” he said. “I should have also told my team and the American public, and I take full responsibility.”
Mr. Austin also said he never told his staff not to inform the White House about his hospitalization.
The defense secretary has long been known as extremely private and media shy.