It should have been a triumphant occasion for Secret Service Director Julia Pierson as she flew aboard Air Force One to the Netherlands for an international summit last week.

President Obama had named her the first female boss in the agency’s nearly 150-year history, and now, three days before her first anniversary on the job, Pierson was accompanying him on a week-long tour of Europe and Saudi Arabia.

But her high-flying moment was short-lived, with the week soon consumed by a scandal involving three of her agents. As Obama opened a series of international meetings, Pierson, 54, moved into crisis mode, calling lawmakers back in Washington to deliver the news: Three members of the president’s protective detail had been dismissed from the trip after one passed out drunk in a hallway of Obama’s hotel.

“She said this kind of behavior would not be tolerated,” Sen. Thomas R. Carper (D-Del.) said of his phone conversation with Pierson. “And she said the president was very disappointed with the behavior.”

For an agency still trying to restore its reputation two years after a highly publicized sex scandal, the incident in the Netherlands brought fresh embarrassment and renewed public scrutiny. Some in Congress have cited the spectacle as further evidence that the Secret Service has failed to eliminate a frat-boy culture marked by lax discipline and little accountability.

Secret Service Director Julia Pierson has not spoken publicly about misconduct by agents on a trip to the Netherlands. (Larry Downing/Reuters)

The events of the past week have thrust Pierson — whose appointment in March 2013 was aimed at setting a new tone — into the spotlight after a year when she sought to quietly implement reforms and restore morale in the 6,500-person agency.

By the end of the week, Carper had invited Pierson, who had remained on the presidential trip, to Capitol Hill to meet with the members of the Senate Homeland Security and Governmental Affairs Committee. The informal briefing will take place Tuesday afternoon, his office said.

“I told my sons it’s okay to make mistakes if they learn from those,” said Carper, the committee chairman. “The rank and file and the leadership of the Secret Service has to learn from theirs.”

The face to face with lawmakers will present a new test for Pierson, who spent three decades in the Secret Service before replacing longtime director Mark Sullivan, for whom she had served as chief of staff for five years. Sullivan retired last year, 10 months after a prostitution scandal involving a dozen Secret Service personnel on a presidential trip to Cartagena, Colombia. His departure left lingering questions about whether his agency had too often looked the other way over misbehavior and had not enforced personal-conduct rules.

On Monday, White House press secretary Jay Carney said Obama believes that all U.S. personnel traveling abroad “must observe only the highest standards. . . . When it comes to occasions when someone working for that agency fails to meet the high standards that are set and the director has imposed, appropriate action needs to be taken, and the president supports that effort.”

Pierson, who has not spoken publicly about the events in the Netherlands, declined to comment for this report.

She remains an opaque figure to the public. Her appointment did not require Senate confirmation, and she has not delivered any public speeches or testified before Congress. She dropped out of a scheduled appearance in Dallas in November to mark the 50th anniversary of the assassination of President John F. Kennedy, citing a work conflict, organizers said.

Pierson joined the Secret Service in 1983 in the Miami field office, and her career got off to an inauspicious start: Her first paycheck was swiped by thieves who had stolen her ATM card and password. The early setback notwithstanding, she worked her way up through the operations, human resources and budget offices to become chief of staff, a position in which she oversaw the agency’s information-technology modernization effort.

Those who have met her say Pierson, who earned money in high school by working as a costumed character at Disney World in Orlando, comes off as charming and gracious. Olivier Knox, a reporter for Yahoo News, described her as “funny and affable” and said she was patient during the filming of several takes of a brief welcome message on a recent video tour of a Secret Service museum in Washington.

George E. Condon Jr., a White House correspondent for National Journal, invited Pierson as his guest to the Gridiron Club dinner March 8 at the Renaissance Washington hotel. Condon said she sent him a handwritten thank-you note afterward.

Privately, however, Pierson was said to have been fuming that evening. The previous day, two Secret Service counter-snipers, dispatched to South Florida for an Obama family trip, were involved in a late-night traffic accident.

A state trooper who responded to the scene smelled alcohol on the breath of the sniper who was driving and administered a field sobriety test, according to a police report. The sniper was released after being cited for failing to yield, but it was enough for Pierson to order both the officers back to Washington before Obama and his family arrived in Florida later that day.

Pierson was so angry that she gathered her deputies and demanded that they make clear to the rank and file that such misconduct would not be tolerated, according to two people familiar with the discussion.

The behavior threatened to undermine the Secret Service’s contention that the Cartagena scandal in April 2012 had not exposed a deeper cultural problem inside the agency. In November, The Washington Post reported that two senior supervisors in the presidential protection division had been reassigned after they allegedly sent inappropriate e-mails to a female subordinate.

The messages were discovered during an internal investigation after one of the supervisors created a disturbance at a Washington hotel when he left a bullet in the room of a female guest. Although the incident occurred in the spring, Pierson and her staff members did not notify the Department of Homeland Security’s inspector general — who was in the middle of a 11 / 2-year cultural review of the agency — until after The Post inquired about it.

In December, the inspector general issued the results of an anonymous survey of Secret Service employees, concluding that there was no evidence of a widespread cultural problem in the agency. In an attached letter, Pierson emphasized that the agency had implemented new guidelines to improve personal-conduct standards.

But she also chided investigators for asking employees to “speculate about the personal, sexual, and potential criminal activities of co-workers” and to respond “through rumor and gossip.”

“This posed a serious concern about the survey content and the value of collecting such speculation,” Pierson wrote.

Acquaintances say her tone illustrated the tough balance she must strike in an agency whose rank and file is embarrassed by the misconduct and dispirited by mandatory budget cuts imposed by lawmakers.

“She has made it very, very clear that this is serious business,” said former Secret Service director W. Ralph Basham, who served from 2003 to 2006 and speaks with Pierson regularly, “and that it reflects on the president and the White House.”