The defiance of Democratic Sen. Robert Menendez, in the face of a 14-count indictment on bribery and corruption charges, is in keeping with a long tradition of officials refusing to leave after everyone else thinks they're past their sell-by date.
Republican Mike Hubbard of Alabama -- one of four state House speakers indicted over the past year -- still holds his position six months after coming up on corruption charges. New York Democrat Charles Rangel, too, remains in office, more than four years after the House formally censured him for various financial irregularities.
In recent years, several governors and mayors have refused to step down despite facing allegations that ultimately led to conviction or popular recall. Illinois Democratic Gov. Rod Blagojevich, for instance, held out until he was impeached, after getting caught on tape trying to sell President Obama's "golden" Senate seat.
In that context, it's no surprise Menendez would want to tough it out, says Brendan Nyhan, an expert on political scandals at Dartmouth College.
"'Time to resign' is a kind of social or media judgment about propriety, not necessarily a political one," he says. "Under some circumstances, politicians can beat charges like this and get re-elected."
It matters that Menendez comes from New Jersey, a state known for patronage and a tradition of corruption. Gov. Chris Christie made his name there as a federal prosecutor putting away more than 100 public officials.
"For those from party machine states or cities, favors are thought to be how politics are done," says Lara Brown, program director at George Washington University’s graduate school of political management.
That's why convicting Menendez, no matter how many hotel and private jet receipts and damning memos the feds have compiled, is going to be tough. Congress would quickly empty out if prosecutors went after everyone who did favors for campaign contributors.
Personal failures -- a sex scandal, drug use, a taste for flamboyant office decoration -- are much more likely to lead to resignation than accusations of financial misdeeds, Brown says. They're more embarrassing and present a black-and-white type of sin.
"The finance rules are certainly a bit more obscure and trying to demonstrate quid pro quo is legally a pretty difficult thing," she says.
Menendez is certainly entitled to his day in court -- and the Justice Department hasn't always made its cases against prominent officials. The senator shows no sign of being interested in a plea bargain, but holding onto office as a bargaining chip often turns out to be the strategy behind initial claims of innocence.
"Just as almost every candidate comes to believe they can win on Election Day, no matter how few people share that point of view, people who have been successful in politics believe they can triumph over this kind of thing, and they sometimes do," says John Weingart, associate director of the Eagleton Institute of Politics at Rutgers University.
But the court of public opinion is a different matter. Someone like Menendez is more likely to leave if his colleagues pressure him out of fear he's damaging the party's brand. "Quite frankly, in the last few years, the Republicans have been much more effective than Democrats in enforcing resignations," Brown says.
More than 250 House members have been caught up in some sort of scandal since Watergate, according to a study by University of Houston political scientist Scott Basinger. Roughly 40 percent of them were gone by the start of the next session, due to resignation or electoral defeat.
But that suggests a healthy majority are able to stick around.
"If Menendez gets convicted, he's going to prison regardless of whether he resigns, and if he isn't convicted, this moment preserves some hope of having a career after a trial," Nyhan says. "That's not an endorsement of him staying in the Senate, of course, but I do think it helps us understand why he might try to tough it out."
[Also by Alan Greenblatt: GOP leaders egg on states to ignore federal laws]
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