As Her Husband Faces Tumult, Jill Biden Is a Protective Force

The special counsel report on President Biden’s handling of classified information has led to questions about the president’s fitness to run for re-election.

Within Mr. Biden’s inner circle, no one knows how taxing the job can be more than Jill Biden, the first lady. At times, she has worked to shield him from the sort of off-the-cuff interactions with reporters that occurred on Thursday evening, when Mr. Biden veered away from scripted remarks and started answering questions.

In January 2022, after Mr. Biden held a two-hour news conference, the first lady dropped by a meeting with the president and his aides. She asked the group, which included the president, why nobody stepped in to stop it, according to a person who was in the room. Where was the person, she demanded, who was supposed to end the news conference?

Officials later apologized to her, according to an account of the episode shared by a person in the room.

“I saw Joe as V.P. and how tough that was,” Dr. Biden said in an interview at her beach home in Rehoboth Beach, Del., in the fall of 2022, referring to Mr. Biden’s eight years as vice president. “But when I see what he does, when I see the table as you get off that elevator and I see a pile like this every single night with briefing books,” she said, placing her two hands apart for emphasis, “and I see him reading and writing, it’s a lot.”

But she said it was worth the effort to stop former President Donald J. Trump from returning to office.

Dr. Biden’s influence is felt in both the White House and the Biden campaign, and there is little doubt among those who know her that one of the first lady’s highest priorities is shielding her husband and family.

She has been directly involved in the hiring of members of his press staff and other senior aides, and is in most of his political meetings. When she does not like something, she points it out. Campaign aides and White House officials privately joke that if Dr. Biden is with him at an event, it is sure to end on time. (Mr. Biden is otherwise often late.)

Some of the people hired by Dr. Biden feel that her East Wing can be a safe haven from an intense workplace, because, as one person close to her put it, no one would dare fire one of her hires.

At least once, she has chided aides who draft speeches for Mr. Biden that she feels are too long-winded: “You see these boots?” she told one former speechwriter, Jeff Nussbaum, pointing toward her heels. “Shorter speeches!”

She was playful when she said it, Mr. Nussbaum recalled in an interview, but he said he knew better than to cast off her criticism as a joke.

When asked about her reputation for bluntly pointing out when she feels like an adviser has made a mistake when it comes to her husband, she answered a question with a question.

“I don’t think it’s a bad thing,” she asked. “Do you?”