WASHINGTON — When an alarmed Representative Kevin McCarthy, the minority leader, called the White House on Jan. 6, 2021, demanding to know why the president of the United States had suggested he was coming to the Capitol while Congress met to certify his election defeat, the person on the other end of the line had just turned 25 years old.
“I said, ‘I’ll run the traps on this,’” Cassidy Hutchinson, now 26, testified this week before the House select committee investigating the Jan. 6 attack, recalling what she had told Mr. McCarthy, Republican of California. “I can assure you, we’re not coming to the Capitol.”
Ms. Hutchinson’s two hours of testimony provided a riveting account of President Donald J. Trump’s mind-set and actions the day of the mob attack and situated the young aide — an assistant by title, but a gatekeeper in practice — at the very center of some of the most sensitive conversations and events of that day.
Sometimes, the interns themselves appear to be running the show.
After the House investigative committee accused Senator Ron Johnson, Republican of Wisconsin, of attempting to hand-deliver to Vice President Mike Pence a slate of false electoral votes for Mr. Trump, Mr. Johnson, 67, blamed the incident on a young underling. He claimed that an unidentified “House intern” had instructed his staff to give the list of fake electors to Mr. Pence.
Other former Trump aides who have appeared in video testimony during the Jan. 6 hearings include Nick Luna, now 35, Mr. Trump’s former body man; Sarah Matthews, now 27, a former deputy White House press secretary; and Ben Williamson, now 29, like Ms. Hutchinson a former aide to Mark Meadows, the final Trump White House chief of staff.
The committee has also featured some of its own young-looking investigators in videos laying out its work.
The relative youth of critical players wielding sway in the government is not a new phenomenon.
Lawrence Higby, who served as a top aide to H.R. Haldeman, President Richard M. Nixon’s chief of staff, was 25 years old when he testified as a key witness during the Watergate hearings.
President Lyndon B. Johnson’s final chief of staff, James R. Jones, was 28 years old when he was appointed to the top job in the White House.
In an interview, Mr. Jones said he was able to rise so high so quickly by following the advice he had received from his boss, W. Marvin Watson, when he joined the White House staff at the ripe old age of 25.
“What I was doing was passing his notes to the president, and he said, ‘You’ll be noticed at the right time. Just do your work now and stay out of the president’s view.’”
Mr. Jones added, “You just had to be at the right place at the right time. I played very low key, I tried to give the credit of successes to others, I didn’t talk to reporters — that’s how I think I made it. I probably would have made a number of key decisions differently with more years on me.”
For the House select committee investigating the Jan. 6 assault, relying on junior aides like Ms. Hutchinson — who held internships with Senator Ted Cruz of Texas and Representative Steve Scalise of Louisiana and then at the White House before joining Mr. Trump’s staff — has been a crucial part of its strategy. With many of Mr. Trump’s senior advisers refusing to cooperate, investigators moved down the organizational chart and quietly turned to at least half a dozen lower-level former staff members who provided critical information about their bosses’ activities.
“We are definitely taking advantage of the fact that most senior-level people in Washington depend on a lot of young associates and subordinates to get anything done,” Representative Jamie Raskin, Democrat of Maryland, told Politico last month, claiming that the young people “still have their ethics intact.”
Representative Liz Cheney, Republican of Wyoming and the vice chairwoman of the committee, compared Ms. Hutchinson favorably to the more seasoned officials who have stonewalled the panel.
“Her superiors — men many years older — a number of them are hiding behind executive privilege, anonymity and intimidation,” Ms. Cheney said in a speech this week. (Her father, the former vice president Dick Cheney, became deputy chief of staff in President Gerald R. Ford’s White House at the age of 33.)
John Podesta, a former chief of staff to President Bill Clinton and a former senior adviser to President Barack Obama, said it has always been the case that in the White House, “there are a lot of people in their late 20s and early 30s” coming from campaigns or from Capitol Hill for jobs with considerable responsibilities.
“They’re expected to perform with fealty to the institution and the Constitution,” Mr. Podesta said. “In this case, it seems like the younger people did a better job than the older people on that front.”
They also have longer careers ahead of them, perhaps making them less willing to tie themselves forever to Mr. Trump’s efforts to overturn the election.
For ambitious young people, government jobs in Washington have long offered a jet-fueled rise to power that the private sector, however lucrative, can’t compete with.
Key Revelations From the Jan. 6 Hearings
Making a case against Trump. The House committee investigating the Jan. 6 attack is that could allow prosecutors to indict former President Donald J. Trump, though . Here are the main themes that have emerged so far:
“You can get a better job as a 24-year-old in Washington in government than you can in a big company,” said Steve Elmendorf, a well-connected Washington lobbyist who early in his career worked as a senior adviser to Representative Richard Gephardt, the Democratic leader. “The West Wing is physically so small, the person who is the 24-year-old is sitting right on top of the principals. Young people end up getting a lot of responsibility, because the principals are so busy and so hard to get to.”
That makes the assistants into gatekeepers who become players in their own right.
“If you can’t figure out how to get Ron Klain on the phone,” he said, referring to President Biden’s chief of staff, “figure out the three people who sit outside his office.”
Adding to the post-collegiate feel of Capitol Hill and the West Wing is the issue of who can afford to work in government, and for how long.
The average age of a House staffer is 31, according to the Sunlight Foundation, a nonprofit dedicated to transparency in government, which noted in a report that the wage gap between the private and public sector “may encourage staff to seek greener pastures while depriving Congress of experience and expertise.”
A chief of staff on average would earn 40 percent more in the private sector than on Capitol Hill, according to the report, and “ex-staffers who become lobbyists can increase their earnings by many multiples.”
During her time in the Trump administration, Ms. Hutchinson, whose title was special assistant to the president for legislative affairs, earned $72,700, according to White House records. The most senior officials earned up to $180,000.
Still, she was there in the West Wing to witness the ketchup-dripping aftermath when Mr. Trump is said to have thrown his lunch against the wall in a rage that William P. Barr, the attorney general, had said publicly that there had been no widespread fraud in the 2020 election.
It was Ms. Hutchinson to whom the White House counsel, Pat A. Cipollone, turned with a dire warning about what would happen if Mr. Trump followed through with his plan to follow his supporters to the Capitol on Jan. 6. “We’re going to get charged with every crime imaginable,” Ms. Hutchinson said Mr. Cipollone told her.
And Mr. Meadows, who was said to have brought Ms. Hutchinson to virtually every meeting he attended, and Rudolph W. Giuliani, Mr. Trump’s personal lawyer, addressed her familiarly as “Cass” as they spoke freely to her about what they were anticipating on Jan. 6.
As she leaned against the doorway to his office a few days before, she testified, Mr. Meadows confided to Ms. Hutchinson, “Things might get real, real bad on Jan. 6.”