The reporter who brought down the Secret Service's director

Washington Post journalist Carol Leonnig has been uncovering the agency's secrets for years.

The Washington Post reporter's scoops brought down the Secret Service's director.

Behind the shocking revelations of incompetence and unprofessionalism that rocked the Secret Service this week is a longtime reporter who has been diligently uncovering the agency's secrets for years.

Carol Leonnig, a Pulitzer Prize-winning investigative journalist who has worked at The Washington Post for nearly 15 years, has broken almost every single story on the agency, a series of shocking reports that on Wednesday resulted in the abrupt resignation of Secret Service Director Julia Pierson. (Pierson called the resignation “painful.”)

In less than a week, Leonnig uncovered three scandals that pushed the agency’s first female leader out the door. First, she reported that Secret Service agents failed to respond for days when a gunman shot the White House residence seven times with a semi-automatic rifle in 2011, smashing a window while Sasha Obama was home. (At first the agency thought the noise was from a car backfiring; then they believed the bullets were from a gang fight they theorized must have occurred on the White House lawn.) 

Leonnig also reported that a knife-wielding man who jumped the White House fence weeks ago made it all the way to the door of the Green Room before an off-duty officer tackled him. The man made it much farther into the building than the agency initially admitted.

Lawmakers pummeled Pierson on Tuesday with Leonnig’s reporting at a House Oversight Committee hearing on the agency’s security failures. After the hearing, Leonnig reported that President Obama recently rode an elevator with an armed felon who was acting strange. (The Washington Examiner broke the story.) It’s unclear if the president was immediately informed of the security breach. Pierson announced her resignation the next day. (UPDATE: The Washington Post acknowledged that the man who rode in the elevator with the president did not have felony or misdemeanor convictions.)

Leonnig’s domination of the story has been so total that the editorial board of The New York Times, The Washington Post’s competitor, cited her stories three times in its editorial calling for an overhaul of the agency.

In an interview with MSNBC this week, Leonnig said Secret Service sources were motivated to talk to her because “they know how great the Service has been in their lifetime and they know what a sacred duty it is to protect the president.” The agents wanted the nation to hear their concerns about how the agency has been sliding down in quality. She added that she believes more Secret Service details and scandals will come out. “Who knows what we will discover as the days go by,” Leonnig said.

The longtime reporter has been on the beleaguered agency’s tail for years: She reported in 2012 that a dozen agents solicited prostitutes while traveling with the president. She also broke the story with colleague David Nakamura in 2013 that a Secret Service agent left a bullet from his service weapon in the hotel room of a woman he had picked up at a bar.

She was part of a team of reporters who won a Pulitzer this year for their work on the National Security Agency’s surveillance program, and she also won a Polk Award for her coverage of former Virginia Gov. Bob McDonnell accepting luxury gifts while in office, which led to a criminal indictment. On her Facebook page, Leonnig thanked her colleagues who weren’t included in the Pulitzer earlier this year but who helped the team win. “Another day that I feel so grateful for the kind of razor-sharp colleagues I get to work with,” she wrote.

This story has been updated to reflect the fact that  the Washington Post incorrectly reported that the man who rode in the elevator with Obama was a felon.

Related Video: