Is Brett Kavanaugh one of the most vicious sexual predators to ever disgrace the federal judiciary? Or a victim of one of the most fevered political witch hunts in American history? It's looking like one of those things must be true. And the American people must be given the chance to discover which.

The space for living with uncertainty between those poles began to collapse on Wednesday, when lawyer Michael Avenatti, he of the Stormy Daniels saga, unveiled a sworn statement from his latest client: a 55-year-old woman named Julie Swetnick. According to The Washington Post, Swetnick is a web developer living in the Washington area who graduated from Gaithersburg High School in Maryland in 1980. She alleges that between 1981 and 1983, when Kavanaugh was a student at Georgetown Preparatory School in Bethesda, Md., she attended many house parties where Kavanaugh and other boys purposely incapacitated girls with alcohol so that they could be taken to a room and gang raped by a "train" of boys who lined up to take their turns.

Kavanaugh dismissed the allegations as "ridiculous and from The Twilight Zone."

Swetnick says that on one occasion she was a victim of the rapes. According to her, both Kavanaugh and Mark Judge, a high school friend of Kavanaugh's who has been named by Christine Blasey Ford as having been present when Kavanaugh allegedly attempted to rape her, attended the party where Swetnick was allegedly attacked. She doesn't specify whether they took part. Judge has denied Ford's claims, and Mother Jones reports that Judge's lawyer says he also denies Swetnick's allegations.

According to a congressional staffer, the Senate Judiciary Committee "has the statement and they are reviewing it," which means that Swetnick's allegation is now theoretically subject to 18 U.S. Code 1001 penalties of up to five years in jail for making any "materially false, fictitious, or fraudulent statement or representation." Ken White, a former federal prosecutor, says that in practice, "the nature of the allegations in the complaint, and their age, would make it extremely difficult to prove they were false, let alone knowingly false," so this does not, despite what many have assumed, necessarily make her statement much more credible than those given to the media. Still, it has been given to the Judiciary Committee, and it cannot be ignored.

Fortunately, unlike the other allegations, this offers many potential lines of investigation. Swetnick states that she told people about these attacks at the time and is aware of others who can corroborate her story — a story that, in any case, should have created dozens of witnesses.

There are real questions that suggest it might not hold up, among them, "How did the media and the FBI, sifting through Kavanaugh's past, miss this?" And Avenatti does not seem to have thoroughly vetted his client before going public. But of course, these things don't prove that she wasn't raped as a young woman, so while Swetnick's sworn statement needs closer examination, it doesn't change the ultimate conclusion: Kavanaugh cannot be confirmed to the Supreme Court with the allegations hanging over his head.

If Republicans are giving any thought to pushing the nomination through without taking adequate time to investigate, they should first search their souls — and then get their heads examined. You do not risk putting a gang rapist on the Supreme Court to "own the libs" or even for the sake of overturning Roe vs. Wade. If basic human decency and a respect for the probity of the courts don't tell you that, then grubby electoral calculations should.

But by the same token, Democrats should stop calling for Kavanaugh's nomination to be withdrawn, as if that could possibly put this scandal to rest. Two days ago, yes, but now the nation cannot afford to punt. Regardless of what it might do to Republican chances of putting a conservative in the seat, or to Democratic chances of retaking the Senate, once Thursday's hearing concludes, the president must reopen the FBI background checks to try to establish the truth of the allegations, from Swetnick, Ford and Deborah Ramirez. If the FBI substantiates them, any criminality should be referred to local prosecutors. If the FBI is unable to substantiate any of them, then despite the lingering questions, Democrats should join Republicans in unanimously confirming Kavanaugh, to signal that some things - both #MeToo and the integrity of the nomination process — are above politics.

Either grave crimes have passed undetected for decades and we must now do our utmost to see them punished, or a new crime is unfolding before our eyes: an attempt to manipulate the composition of the highest court of the land through the strategically timed release of unfalsifiable accusations of sexual assault. Either way, it's too late for a political solution. This is now about preserving the integrity of the American justice system; it can't be brushed away with "politics ain't beanbag." At this point, it's more like Fiat justitia ruat clum: Let justice be done though the heavens fall.

Megan McArdle is a Washington Post columnist.

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