WASHINGTON // It is an agency that, according to its own motto, strives to be "worthy of trust and confidence".
But a sex scandal has shattered the image of the US secret service - all sharp suits, dark sunglasses and unflappable sense of duty - and politics is ensuring that the story won't go away.
The scandal has mostly surrounded the potential implications for national security. But deeper questions have also been raised about the conduct of a dozen agents, as well as several military officers, who were implicated in an alcohol-fuelled night with local prostitutes in Cartagena, Colombia ahead of a state visit by Barack Obama, the US president, on April 13.
The advance team did not break any laws. Prostitution, in designated areas, is legal in Colombia. The White House has been adamant that at no time was the president - whose personal security is the purview of the secret service - in any danger.
But the incident was an "unprecedented" breach of security by the agency that could have had serious implications for national security, said Ronald Kessler, author of the 2009 book In the President's Secret Service.
"First of all, this involves the president. Secondly, it involves the possibility of blackmail if these prostitutes had been in league with terrorists or the Russians," he said on Monday.
The White House has been keen to downplay the incident. Mr Obama described the agents involved as "knuckleheads" and joked about newly tightened rules of conduct for the agency at a recent dinner for White House correspondents, saying he had to leave early to chaperone his personal detail.
But in doing so, the administration has brushed aside deeper question about the actions themselves in a "boys-will-be-boys" culture, said Lori Handrahan, a professor at American University in Washington. These agents were "purchasing women" and their behaviour should be considered unacceptable under any circumstances, Ms Handrahan said.
"If Obama came out swinging, saying this is a very serious issue, there wouldn't be much of a story after a few days."
Instead, she said, Mr Obama has provided ammunition to his Republican rivals who can continue to criticise the administration's response as weak. While Mr Obama was not responsible for the agents' actions, he was responsible for his reaction, she said.
And Republicans were right that the president "is not demonstrating leadership and therefore he is at fault", she said.
Eight secret service officers have been fired and three disciplined so far, while a dozen military personnel have had their security clearances suspended in an unfolding internal investigation.
The agency was also looking into whether agents hired prostitutes and strippers in El Salvador in advance of the president's trip there last year. Rules for alcohol consumption and fraternising with foreigners have also been tightened.
Republican pressure has seen the internal investigation dramatically expanded. Four congressional committees were looking into the incident, and on Monday, the department of homeland security, which oversees the secret service, announced that its top watchdog would probe the adequacy of the agency's own investigation.
This will keep the spotlight on an agency that has stumbled publicly in the past few years. In 2009, agents mistakenly let in a couple of professional party crashers to a dinner at the White House, at which a third uninvited guest also managed to gain entrance.
And during a state visit to Australia last year a detailed account of Mr Obama's movements was found in the gutter by an Australian newspaper.
More reports were surfacing of similar behaviour and unprofessionalism, suggesting there is an endemic problem in the agency. According to an Associated Press report yesterday, the agency was trying to stem the flow of salacious detail and has asked agents and former agents to keep away from the media.
Mr Kessler, who spoke to more than 100 agents, both current and former, in researching his book, said the Colombia incident was a symptom of a larger agency management problem.
"There is a laxness that goes all the way to the top, and that culture radiates down to agents. And when they are idiots, as these guys were, they figure, 'well, management is doing it, I can do whatever I want'," he said.