US Secret Service director Julia Pierson has demoted the supervisor of one of the agency's largest divisions and reassigned nearly two dozen of its agents, according to three people familiar with the moves.
They are part of a broader clean-up effort in the wake of embarrassing drinking incidents on two recent presidential trips.
The agency has also ordered stricter rules on alcohol for the division, known as special operations, forbidding them from drinking within 12 hours of duty and 24 hours before the president's arrival at any trip location.
Five employees of special operations were implicated in misconduct ahead of trips by US President Barack Obama last month to the Netherlands and Miami. The division is central to the agency's efforts to ensure the safety of Obama and his family.
A Secret Service spokesman declined to discuss the removal of Dan Donahue as the special agent in charge of the division.
"Personnel are being reassigned as a result of staffing rotations and as a result of assessments made after two recent incidents of misconduct," Ed Donovan said.
Donahue ordered the tougher drinking rules in the wake of news coverage of alcohol-fuelled incidents involving his employees in the Florida Keys and the Netherlands last month, according to an official. Mike Rolin, the former deputy supervisor overseeing the Secret Service's Washington field office, had taken over the special operations division, the official said.
Both men declined requests for comments.
The agency has been struggling for two years to recover from a drinking-and-prostitution scandal ahead of Obama's visit to Cartagena, Colombia, for a regional summit in April 2012. The latest incidents have brought fresh embarrassment to the service and harsh new questions for Pierson in Congress.
Senator Ronald Johnson, the senior Republican on the Homeland Security and Government Affairs investigative subcommittee, said on Tuesday that he remained concerned about the Secret Service's problems and whether the new rules would end them. Agency policy clearly did not allow agents to hire prostitutes or abuse alcohol, he said, yet such incidents had happened multiple times.
"While these rules are a step in the right direction, the real question is how often does this type of misconduct occur, and who is held accountable when it is reported?" Johnson said. "The examples we have from Cartagena, Miami, and Amsterdam all involve a third party recognising and reporting misconduct by USSS employees - not self-reporting within the agency. An accurate assessment of how prevalent this conduct is within the USSS is long overdue."
In the Netherlands, three agents responsible for protecting Obama on a trip to a nuclear summit there on March 24 were sent home after going out drinking the Saturday before. One agent had been found passed out in the hallway of his hotel on Sunday morning, where Obama was scheduled to arrive the next day.
Pierson was already unhappy about another incident of misconduct in Florida in early March, when two counter-sniper officers suspected of drinking had a car accident just before the first family's arrival in the area.