As soon as a Senate hearing into the Secret Service prostitution scandal began, it was clear there would be no rehabilitation of the agency’s reputation.

In fact, by the time the Homeland Security and Governmental Affairs Committee session concluded, skeptical senators on both sides of the aisle had painted Director Mark Sullivan as a good administrator but one hopelessly naive about what his agents do away from home.

Of course, there is no proof that the scandal involving a dozen agents who allegedly patronized prostitutes, while advancing President Obama’s trip to Colombia, represents standard operating procedure.

But the senators also don’t believe it was a one-time fling.

“It is hard for many people, including me, I will admit, to believe that on one night in April 2012 in Cartagena, Colombia, 12 Secret Service agents there to protect the president suddenly and spontaneously did something they or other agents had never done before, which is gone out in groups of two, three or four to four different nightclubs or strip clubs, drink to excess, and then bring foreign national women back to their hotel rooms,” said Chairman Joseph I. Lieberman (I-Conn.).

Questions reflected a persistent concern: Instead of an aberration, does Cartagena indicate a culture of loose living by agents on the road?

Senators repeatedly referred to a story in Wednesday’s Washington Post. With juicy details, Carol D. Leonnig and David Nakamura reported that “current and former agency employees say sexual encounters during official travel had been condoned under an unwritten code that allows what happens on the road to stay there.”

Sullivan, who apologized for the misconduct, insisted that is not the case: “I just believe extremely — very strongly that this just is not part of our culture.”

Repeated statements like that did not sit well with Sen. Susan Collins (Maine), the panel’s ranking Republican.

“The only answer of his that disturbed me today,” she told reporters after the hearing, “was that he kept saying over and over again that he basically does think this is an isolated incident, and I don’t think he has any basis for that conclusion.”

Perhaps more will be known after Charles K. Edwards, acting inspector general for the Department of Homeland Security, conducts a full, independent investigation of the incident, which the senators had to push him to do.

One conclusion Lieberman reached is that no one would know about the Cartagena hookups except for an agent’s loud dispute over his bill for sex.

“If one of the agents had not argued with one of the women about how much he owed her,” Lieberman said, “the world would never have known this sordid story.”

Sullivan disagreed, saying he thinks other agents would have told. Yet, Sullivan also said a survey of employees found that less than 60 percent of them would report an incident of unethical behavior.

“Forty percent is a very high percentage that wouldn’t report,” said Sen. Ronald H. Johnson (R-Wis.), who speculated about a “code of silence” within the Secret Service.

If Cartagena is not part of the agency’s culture, it also is not a totally isolated event. Over the past five years, Lieberman said, “there appear to have been five cases that are directly relevant to what happened in Cartagena and therefore potentially noteworthy, three allegations involving inappropriate or undocumented contact with a foreign national, one allegation of contact with a prostitute, and one allegation of non-consensual sex.”

Citing information from Edwards’s office, Lieberman said at least three agents were disciplined for “and here I’m quoting — ‘partying with alcohol with underage females in their hotel rooms while on assignment at the 2002 Olympics.’”

In another case, an on-duty agent picked up an undercover police officer posing as a prostitute in 2008.

Not all of the allegations were proved.

But despite the skepticism, and the other cases he listed, Lieberman said, “We do not yet find evidence at all sufficient to justify a conclusion of a pattern of misconduct or a culture of misconduct.”

Yet, the fact that most of the dozen agents in Cartagena made no attempt to hide their trysts suggests to Collins “that this kind of conduct has been tolerated in the past.”

Sullivan insisted the agency has zero tolerance for such behavior, which he is at a loss to explain.

“Between the alcohol — and I don’t know, the environment,” he said, “these individuals did some really dumb things.”

For Joe Davidson’s previous columns, go to