This post has been updated.

The announced departure of three U.S. Secret Service employees tied to a prostitution scandal came on the same day that lawmakers formally requested a full accounting of the unfolding scandal by May 1.

(Win McNamee/Getty Images)

Last week’s incident “is troubling because Secret Service agents and officers made a range of bad decisions, from drinking too much, to engaging with prostitutes, to bringing foreign nationals into contact with sensitive security information, to exposing themselves to blackmail and other forms of potential compromise,” Reps. Darrell Issa (R-Calif.) and Elijah Cummings (D-Md.), who lead the committee, wrote in a letter to Sullivan.

“Your swift and decisive action in response to this scandal has given us confidence that the agency will complete a thorough investigation and take steps to ensure that similar lapses in judgment will never again jeopardize the important work of the U.S. Secret Service,” the lawmakers said.

In an interview Wednesday, Cummings said the departure of at least three employees didn’t surprise him.

“The agency is embarrassed. I believe that the agency will be harder on itself than members of Congress could ever be,” Cummings said.

The Maryland lawmaker said Secret Service agents “don’t even want people to imagine that their standards are not the highest standards possible. There’s a pride that comes with this agency and a reputation that they’ve earned over many years and there’s a level of trust that they’ve established with the public and the president and the vice president, all the people they guard, and the American people. It’s an agency with people who consider it an honor to be a part of.”

Meanwhile, Congress likely will have its first public discussion of the scandal next Wednesday, when Homeland Security Secretary Janet Napolitano testifies at a Senate Judiciary Committee hearing on general oversight matters at her sprawling department, which includes the Secret Service. Though Napolitano doesn’t oversee day-to-day operations of the agency, aides say she has been briefed regularly on the scandal and subsequent investigation.

Sullivan and top agency officials have briefed several lawmakers and their staffs each day this week. According to congressional officials familiar with the investigation, the agency has concluded that each of the 11 agents involved in the incident brought a woman back with him to the Hotel Caribe, but that different groups of agents and military personnel visited different clubs on the night of April 11.

The Secret Service continues to lead its own investigation, and agency officials remain in Colombia, where they are attempting to speak with the woman involved; they also are interviewing staffers at the Hotel Caribe and reviewing hotel lobby surveillance tapes.

Guns, radios, handcuffs and any sensitive documents related to Obama’s trip were not in the rooms of the agents at the time of the women’s visits, but instead were held securely in another room until their shifts began, congressional officials said. It is not clear whether at least some of the agents had early knowledge of the security plans for Obama’s attendance at the Summit of the Americas, the officials said.

The agency has no policy regarding visitors to hotel rooms, but it is reviewing the policy on interacting with foreign nationals, the congressional officials said. The lack of a policy on hotel guests could complicate the agency’s ability to discipline the eight remaining employees, one official said.

The 11 agents involved in the incident all flew out of Colombia together last Friday morning on a commercial flight, congressional officials said. When they arrived in Miami, a supervisor instructed the agents to contact their individual supervisors. They then all boarded a flight Friday afternoon for Washington, where they faced further interviews and polygraph tests.

Follow Ed O’Keefe on Twitter: @edatpost

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