WASHINGTON— The Senate Ethics Committee that has issued no public punishment against a senator in a decade is suddenly taking on three highly charged ethics cases that could set new precedents for congressional behavior.

The panel could also be a tool to simply bury the cases until the public storm passes.

Two marquee cases against sitting members of Congress landed in the lap of the committee this week — one involving sexual misconduct allegations against Minnesota Democratic Sen. Al Franken and a second turning on corruption charges aimed at New Jersey Democratic Sen. Robert Menendez.

Sen. Al Franken, D-Minn., apologized Thursday after a Los Angeles radio anchor accused him of forcibly kissing her during a 2006 USO tour and of posing for a photo with his hands on her breasts as she slept.

A third case could be coming soon, depending on the outcome of the Dec. 12 Alabama special election, where GOP candidate Roy Moore’s campaign has been rocked by allegations that he pursued sexual relationships with teenage girls nearly 40 years ago.

The committee, which is made up of up of three Republican senators and three Democrats, regularly disposes of ethics complaints quietly and summarily and long after the case has left the front pages. But it will be under intense scrutiny as it takes up the glaring issue of sexual harassment. 

“I think we’re sailing into new waters here,” said Stanley Brand, a lawyer who has advised the committee and represented lawmakers under investigation in previous cases. “The public pressure is going to be great.”

And the political consequences could be far-reaching. Here’s a look at the allegations and key questions the ethics committee will have to confront.

Franken

On Thursday, a news anchor for a Los Angeles radio station, Leeann Tweeden, accused Franken of forcibly kissing and groping her in 2006, when they were on an overseas USO Tour to entertain American troops. She released a jarring photo of Franken, a former Saturday Night Live star, appearing to grab her breasts while she was sleeping on the cargo flight home. Franken apologized to Tweeden, and said he would cooperate with an ethics committee inquiry, which lawmakers in both parties have demanded.

The ethics committee has not announced any action yet, and a spokesperson did not return a message seeking comment. But experts say the case presents several thorny questions.

First, Franken was not in the Senate in 2006. The ethics committee has broad jurisdiction to consider conduct that occurred before a senator was elected, but it's unusual.

Take, for example, the salacious allegations against former Sen. David Vitter, R-La., who was publicly linked to the leader of a prostitution ring. The ethics committee dismissed a complaint against Vitter in 2008, in part because it happened before he was elected.

And Franken would not be fighting allegations that he violated a specific Senate rule. Instead, the question would be whether his actions cast the Senate in a bad light.

“There is the overarching standard of conduct that a member and staff of the Senate shall not engage in conduct that reflects discredit on the institution,” said Rob Walker, a Washington ethics expert and former counsel to the House and Senate ethics committees

But it would be rare, if not unprecedented, for a lawmaker to face a stand-alone alleged violation of that "discredit" standard, since it’s normally tacked on to other charges, Brand said.

And those aren’t the only twists in the Franken case.

“The senator himself has asked the committee to look into (his) conduct,” Walker said.  That means the proceedings could be less adversarial, resulting in a negotiated settlement that gets hashed out privately.

Critics say the Senate ethics committee is a bit of a “black box,” said Lisa Gilbert, vice president of legislative affairs for Public Citizen, a left-leaning government watchdog group.

“The public has been asked to tolerate secrecy when it comes to congressional ethics over and over again,” Gilbert said.

The panel's internal deliberations are often secret, and the punishments are often mild. She is not optimistic than anything with change now, even in the face of public pressure. 

"Members policing other members can be problematic," she noted.

But with sexual abuse allegations felling public personalities in Hollywood and elsewhere, closed proceedings in Congress could spark a public outcry against Franken or the members of the committee.

“It is a new day,” said Walker. “The scales have fallen from the eyes of public officials and the public on matters of sexual harassment.”

More: Analysis: When it comes to Al Franken assault allegations, Congress appears united

Menendez:

U.S. Sen. Bob Menendez fights tears as he speaks to reporters outside Martin Luther King Jr. Federal Courthouse after U.S. District Judge William Walls declared a mistrial in Menendez's federal corruption trial, Thursday, Nov. 16, 2017, in Newark, N.J. (AP Photo/Julio Cortez)

A jury in the federal corruption trial against Menendez  deadlocked on all 18 counts against the New Jersey Democrat. Prosecutors had accused Menendez of doing official favors for Salomon Melgen, a wealthy Florida eye doctor and longtime friend, in exchange for luxury vacations, free flights on Melgen’s private jets and more than $700,000 in political contributions. 

The Senate Ethics Committee announced Thursday  that it would reopen a probe started in 2012, which had been put on hold while the Justice Department investigated.

This case fits more squarely into the committee’s bailiwick. Menendez could face punishment, up to possible expulsion, from his colleagues if they decide he violated Senate rules, including one that requires the disclosure of gifts such as the flights on Melgen’s jet.

Walker notes that the standard for a conviction in court is beyond a reasonable doubt, while the standard for the ethics committee is lower: clear and convincing evidence.

"It’s possible someone could be found not guilty at a criminal trial, and the committee could still determine clear and convincing evidence of an ethics violation. I think the committee could, and frankly should, conduct its own investigation," Walker said.

Brand said the federal trial record could provide fodder for the committee, but also a counterpoint for the senator. “Menendez has an argument, ‘Hey look the jury couldn’t conclude anything against me,’” Brand said. “There’s a different standard of proof, but it should count for something.”

Marc Elias, a Washington attorney handling the ethics matter for Menendez, said the senator is ready to answer all the committee's questions.

“Our posture was and remains to be fully cooperative with the ethics committee,” Elias said.

More: Mistrial declared in Bob Menendez trial after jury deadlocks

More: Senators say they'll welcome Menendez back, but ethics probe looms

Moore

Former Alabama Chief Justice and U.S. Senate candidate Roy Moore waits to speak at a press conference, Nov. 16, 2017, in Birmingham, Ala.

 Moore is the GOP nominee in a Senate special election in Alabama, set for Dec. 12. The Washington Post reported last week that the 70-year-old Moore pursued sexual or romantic relationships with several teenage girls when he was in his 30s. Since then, more women have come forward with other allegations, including one who said Moore assaulted her in his car when she was 16.

Senate Majority Leader Mitch McConnell, R-Ky., has said Moore should drop out of the race, and told the Wall Street Journal on Wednesday that if Moore wins, he will immediately face an ethics inquiry. Other Republican lawmakers have suggested the controversial former judge could face expulsion from the chamber.

All this before Moore has even faced the voters of Alabama.

If he wins, it would be legally difficult and politically risky for the Senate to try to overturn that democratic outcome.

“The people of Alabama are entitled to choose who they will, even if the rest of us don’t like him,” Brand said. If Moore wins in the face of the current allegations, it is considered “pardon of the conduct by the electorate.”

And like the Franken case, the allegations against Moore occured well before he arrived in Washington and don't involve a specific Senate rule violation. It could also set up a constitutional clash over what makes someone “unfit” to serve in the Senate.

Brand noted that the Supreme Court has ruled the only reason a duly elected official can be excluded from Congress if that person doesn’t meet the constitutional requirements of age, residence and citizenship.

“The Congress can’t just add new things post-hoc,” Brand said.

Contributing: Paul Singer and Nicholas Pugliese

More: White House on Roy Moore: 'The people of Alabama should decide' his fate

More: Mitch McConnell says Roy Moore 'not fit' to serve in the Senate, won't rule out expulsion option