So many Washington stories begin with a fender-bender. This is one of those stories.

Earlier this month, two Secret Service agents, including a senior member of the detail charged with protecting President Barack Obama, drove a government car into one of the barricades surrounding the White House compound.

The two men had spent much of the evening at a going-away party for departing Secret Service spokesman Edwin Donovan and returned to the White House perimeter sometime after 10:30 p.m. on March 4 amid a suspicious package investigation, according to The Washington Post’s Carol Leonnig.

The two, with overhead lights flashing, drove into the barrier, and, as Leonnig notes: “Investigators who have reviewed the tape of the incident say the pair either drove very close to or over the suspicious item wrapped in the shirt, one law enforcement official said.”

Er, not good. And especially bad given the past few years for the agency, which has endured embarrassment surrounding agents’ use of prostitutes while on an advance trip for the president in Colombia; questions about its handling of White House intruders after a man hopped a perimeter fence and made it deep into the building; and frustration over its late reaction to several gunshots that hit the personal residence.

That series of calamities led to a house-cleaning at the top of the Secret Service. Joseph Clancy, who at one time led Obama’s personal protection unit, was installed as the agency’s new director last month. But changing the faces in charge doesn’t appear to have had much effect just yet.

The Secret Service, for crashing into yet another public relations barrier, you had the worst week in Washington. Congrats, or something.

Chris Cillizza covers the White House for The Washington Post and writes The Fix, its politics blog.