From its earliest days, the administration of US President Joe Biden has pledged to restore truth and transparency to the federal government, but now it is facing a wave of criticism and questions about its credibility after Defense Secretary Lloyd Austin's hospitalization was kept secret for days, even from the White House.

The controversy has prompted the government to review rules put in place to prevent such incidents, while the Pentagon is scrutinizing its procedures after the unusual lapse, which left even Austin's top deputies unaware of his condition for days.

Senior congressional Republicans are investigating whether Austin flouted legal requirements to notify Congress, and Biden administration officials are upset that Austin did not provide the information, a mistake they believe undermines the president’s message of restoring capacity through his administration.

The prolonged attention on the health secrets of a senior official is also fueling controversy over President Biden's own health, as he is the oldest president in history to seek re-election and faces frequent questions and concerns from voters about his age.

Questions about transparency and the health of senior officials have left the White House in a bind for days as the election year begins, and have given President Biden’s political opponents an opportunity to question whether his administration will live up to its commitment to competence.

After days of silence about Secretary Austin’s health, the Pentagon revealed on the afternoon of January 9 that he had prostate cancer. Mr. Austin, 70, was admitted to Walter Reed National Military Medical Center on December 22 and underwent surgery to treat the disease, but a week later developed a urinary tract infection and was admitted to intensive care.

There is no policy in the Biden administration stipulating how to handle absences by Cabinet officials, although the White House is expected to be informed about such cases, according to people familiar with the matter.

Although there is no legal requirement for officials to disclose their medical histories, it has become common practice for presidential candidates, vice presidents and current officials to release such information.

Public disclosure of a cabinet official's absence also varies across federal agencies. For example, the U.S. Department of Justice announced in 2022 that Attorney General Merrick Garland would undergo surgery to remove enlarged prostate tissue a week before the procedure.

Transportation Secretary Pete Buttigieg took a leave of absence after adopting twins in 2021, but the leave was not publicly disclosed until he returned to work.

Cedric Leighton, a retired US Air Force colonel, noted that the US military's chain of command runs from the president through the secretary of defense to combatant commanders, who then execute orders that could include command and control of any use of nuclear weapons.

It is “imperative” that the president, top administration and military officials, members of parliament and even key allied counterparts be informed of temporary absences, he said.

“It is highly unusual for any cabinet secretary to not notify the president, the White House chief of staff or the National Security Council of any absence, especially for health reasons,” Mr. Leighton said.

Secretary Austin's case has sparked bipartisan criticism from lawmakers, who have raised questions about how his condition could have been kept secret from the White House, Capitol Hill and the public.

Mississippi Sen. Roger Wicker, the top Republican on the Senate Armed Services Committee, said Austin's failure to disclose his condition to key lawmakers and hand over duties to Deputy Defense Secretary Kathleen Hicks was a "clear violation of the law."

Sen. Richard Blumenthal said he was not satisfied with the Pentagon's explanations and called on the Senate Armed Services Committee to look into the matter, possibly holding a hearing.

“He owes Congress and the American people additional information to assure us that he can continue to serve,” said Sen. Blumenthal.