It’s the first federal bribery indictment of a sitting senator in almost a quarter century, and the defendant is among the most combative and combustible Democrats in the Capitol. So why have Republicans spent the better part of the past two weeks with their hands over their mouths?  

There are four plausible reasons for their relative silence about the travails of Robert Menendez. They boil down to concerns about political expedience, foreign policy, self preservation and campaign finance. At a minimum, the GOP may have concluded it best to stand clear while New Jersey’s senior senator twists slowly, but very publicly, in the prosecutorial wind. Calling for him to resign or otherwise piling on, especially before he’s had his day in court, won’t really add to the attention his case will be getting — and it could readily damage the party by magnifying the perception that petty partisan motives lie behind most everything Congress does.  

Just beyond that rationale is this reality for congressional Republicans: By coincidence, Menendez is a significant helpmate these days to advancing one of their most important objectives of the year — combating the Obama administration’s efforts on the international front.  

Though he’s decided to live with precedent and stand aside as the ranking Democrat on Foreign Relations so long as he’s facing potential prison time, Menendez has made clear he has every intention of speaking out at his usual volume on global affairs, and no more passionately than against President Barack Obama’s efforts to normalize relations with Cuba and finalize the nuclear agreement with Iran . The GOP has little reason to discredit someone who gives their attacks on the president a rare bit of bipartisan veneer.  

The third reason for Republicans’ reticence suggests they’re following the guidance of a favored proverb of parents: People who live in glass houses shouldn’t throw stones .  

GOP leaders clearly remember the last time a voluble old-school senator was indicted over his cozy relationship with a friend and political ally with business interests reliant on the federal government — because he was one of their own, the late Ted Stevens of Alaska, just seven years ago.  

They remain furious about how Stevens was brought down. The conviction was thrown out because of prosecutorial misconduct, but that was five months after Stevens had been defeated for re-election on the heels of his guilty verdict. Beyond that, there remains a lingering bipartisan realization that what happened to him could happen to almost any of them. In other words, they’re all routinely exposed to temptations that start down the same road that got Stevens in trouble, and that today have Menendez confronting eight felony bribery charges and 15 other criminal counts.  

That’s because, day in and day out, every member of Congress has to make distinctions among genuine personal friends, pals and benefactors from their political lives, and for-profit favor seekers masquerading as would-be intimates. Then each lawmaker is called on to assess which potential actions affecting those people would be out of true fealty, which would be justifiable as constituent service, which would further the lawmaker’s own ideological or public policy goals — and then might nonetheless create at least the appearance of a quid pro quo, no matter how pure the motive to be helpful. Lawmakers who are naive or have a tin ear to the sound of potential impropriety, or who permit a politician’s default aggressiveness to prevail over reasonable caution, are at least supposed to be smart enough to empower their staffers to safeguard their reputations.  

At a minimum, members need to be wary of doing something that federal prosecutors find particularly easy to use against lawmakers in ethics cases: Lying on their financial disclosure forms, most frequently by omitting gifts from people who aren’t allowed to be generous toward lawmakers. (The only crime Stevens was accused of was filing seven annual reports that omitted gifts from an Alaska oilman; one felony count against Menendez says he concealed from the Senate Ethics Committee all the largesse from his co-defendant in the purported bribery scheme, Florida eye surgeon Salomon Melgen.)  

Many senators, Republican as well as Democrat, will want to give the benefit of the doubt to a colleague of their 100-member club, the phrase “there but for the grace of God go I,” ringing in their ears. (Some lawmakers will also note warily how the indictment mentions 13 different Menendez congressional aides in the middle of his dealings with Melgen — led by Danny O’Brien, who left the Hill in January after six years as the senator’s top staffer. The indictment makes clear O’Brien will be a key witness for the government.)  

For Menendez’s compatriots, the 68-page document could be read as a colorful tale of poor judgment: A senator goes several extra miles to advocate for a close family friend of long standing, not only on a $9 million Medicare overbilling dispute and an investment in a cargo screening business, but also in seeking visas for no fewer than three of his buddy’s girlfriends.  

Along the way, the ophthalmologist’s expressions of affection for the senator include 18 trips on private jets, two first-class airline tickets, use of a resort villa in the Dominican Republic, three nights in a $1,600 hotel suite in Paris, a limousine ride in New York and an 18-holes-and-a-steak-dinner excursion to West Palm Beach, Fla.  

But that wasn’t the half of it — and it’s Melgen’s most generous gestures that may have done the most to prompt the Republican silence.  

In the six months before the 2012 elections, he donated $8,000 to Democratic Sen. Amy Klobuchar of Minnesota, allegedly to help Menendez repay a political favor from her, and $143,500 to state and local political committees helping Menendez’s re-election bid in New Jersey. But those gifts paled next to the $600,000 Melgen delivered (earmarked for the benefit of Menendez) to Senate Majority PAC.  

Operated by members of Democratic Leader Harry Reid’s inner circle to help their party hold control of the chamber, it was among the new generation of super PACs created after the Supreme Court’s Citizens United decision allowed unlimited contributions to groups operating independently from parties or campaigns.  

The majority opinions in that case, and the subsequent McCutcheon case further relaxing the regulation of money in politics, have created new constitutional protections for campaign donations in the pursuit of political influence — thereby making it more difficult than ever for prosecutors to prove bribery by establishing an explicit connection between a particular gift and a particular official act.  

And it is the Republicans, far more than their partisan rivals, who want to protect the new campaign finance status quo — even if that makes it tougher to win the historic conviction of a very prominent Democrat.  

Related:

Menendez Indicted on Federal Corruption Charges


Will Menendez Staffers Be Forced to Testify Against the Boss?


The 114th: CQ Roll Call’s Guide to the New Congress


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