The lawmaker leading a probe into the Secret Service prostitution scandal said Wednesday that the agency's records indicate agents have been involved in dozens of "troubling" episodes in recent years. 

"We can only know what the records of the Secret Service reveal," Connecticut Sen. Joe Lieberman said in opening the first Senate hearing into the matter. And those records, however incomplete, show 64 instances of allegations or complaints of sexual misconduct made against Secret Service employees in the last five years, he said.

Lieberman called on insiders to come forward with what they know, as investigators try to determine whether a culture of misconduct has taken root in the storied agency.

Secret Service Director Mark Sullivan, speaking to the inquiry, apologized for the behavior of the employees in Colombia. But his assertion that the agency has a "zero tolerance" policy on such conduct did not convince the lawmakers, who brought more allegations to light.

It is hard for many people, including me, to believe that on one night in April 2012 in Cartagena, Colombia, 11 secret service agents — there to protect the president — suddenly and spontaneously did something they or other agents had never done before.

- Sen. Joe Lieberman

Lieberman cited three complaints of inappropriate relationships with a foreign national and one of "non-consensual intercourse," which he did not elaborate on. Sullivan said that complaint was investigated by outside law enforcement officers who decided not to prosecute.

Sullivan also told the committee an agent was fired in a 2008 Washington prostitution episode, after trying to hire an uncover police officer.

Many of the other complaints cited by Lieberman involved agency employees sending sexually suggestive emails.

Republican Sen. Susan Collins of Maine told the hearing several small groups of Secret Service employees separately visited clubs, bars and brothels in Colombia prior to a visit by President Barack Obama last month and engaged in reckless, "morally repugnant" behavior.

Collins said the employees' actions could have provided a foreign intelligence service, drug cartels or other criminals with opportunities for blackmail or coercion threatening the president's safety.

And she challenged early assurances that the scandal in Colombia appeared to be an isolated incident. She noted that two participants were Secret Service supervisors — one with 21 years of service and the other with 22 years — and both were married. Their involvement "surely sends a message to the rank and file that this kind of activity is tolerated on the road," Collins said.

"This was not a one-time event," said Collins, the senior Republican on the Senate Homeland Security and Governmental Affairs Committee. "The circumstances unfortunately suggest an issue of culture."

Lieberman didn't go that far, saying a historical pattern cannot be established from what is known so far.

But he said: "It is hard for many people, including me, to believe that on one night in April 2012 in Cartagena, Colombia, 11 secret service agents — there to protect the president — suddenly and spontaneously did something they or other agents had never done before; that is to say, gone in groups of two, three or four to four different night clubs or strip joints and drank to excess and bring foreign national women back to their hotel rooms."

The misbehavior became public after a dispute over payment between a Secret Service agent and a prostitute at a Cartagena hotel on April 12. The Secret Service was in the coastal resort for a Latin American summit before Obama's arrival.

Collins said several small groups of agency employees from two hotels went out separately to clubs, bars and brothels and they "all ended up in similar circumstances."

"Contrary to the conventional story line, this was not simply a single, organized group that went out for a night on the town together," Collins said.

Senators focused on whether the Secret Service permitted a culture in which such behavior was tolerated. Homeland Security Secretary Janet Napolitano has testified previously that she would be surprised if there were other examples, but senators have been skeptical.

Sullivan told senators the behavior in Colombia wasn't representative of the agency's nearly 7,000 employees. "I can understand how the question could be asked," Sullivan said, calling his employees "among the most dedicated, hardest working, self-sacrificing employees within the federal government."

He also told senators that Obama's security was never at risk. The officers implicated in the prostitution scandal could not have inadvertently disclosed sensitive security details because their confidential briefing about Obama's trip had not taken place.

"At the time the misconduct occurred, none of the individuals involved in the misconduct had received any specific protective information, sensitive security documents, firearms, radios or other security-related equipment in their hotel rooms," Sullivan said.

Sullivan has survived professionally so far based on his openness about what happened. Senators were not expected to ask for his resignation, and the acting inspector general for the Homeland Security Department, Charles K. Edwards, gave Sullivan high marks for integrity.

Edwards, who estimated that the early stages of his own investigation would be finished before July 2, said the Secret Service "has been completely transparent and cooperative."

"The Secret Service's efforts to date in investigating its own employees should not be discounted," Edwards told senators. "It has done credible job of uncovering the facts and, where appropriate, it has taken swift and decisive action."

The White House on Tuesday reasserted its confidence in Sullivan. Obama "has great faith in the Secret Service, believes the director has done an excellent job," White House spokesman Jay Carney said. "The director moved very quickly to have this matter investigated and took action very quickly as a result of that investigation."

A dozen Secret Service officers and supervisors and 12 other U.S. military personnel were implicated. Eight Secret Service employees, including the two supervisors, have lost their jobs. The Secret Service is moving to permanently revoke the security clearance for one other employee, and three others have been cleared of serious wrongdoing. Sullivan told the lawmakers that two employees who originally resigned now are fighting to get their jobs back.

Prostitution is legal in Colombia, but Sullivan quickly issued new guidelines that made it clear that agents on assignment overseas are subject to U.S. laws.

Sullivan said he directed Secret Service inspectors to investigate reports of similar misconduct in San Salvador. After 28 interviews with hotel employees and managers, State Department officials and others, "no evidence was found to substantiate the allegations," Sullivan said.

This week the Drug Enforcement Administration said the Justice Department's Office of the Inspector General was investigating possible misconduct by two or more agents in Colombia. Collins revealed that the case involved at least two DEA employees who entertained female masseuses in the Cartagena apartment of one of the DEA agents. The investigation is unrelated to the Secret Service scandal but is based on information provided to the DEA by the Secret Service.

Based on reporting by the Associated Press.

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