The Constitution says that we are supposed to have a Supreme Court, and that its members should serve “during good behavior.” But that’s about it.

The rest – who belongs on the court and who doesn’t – is left up to us, and once a generation, we have an argument about where to draw the line.

In 1937, Hugo Black was confirmed as a justice even though he had been a member of the Ku Klux Klan. President Franklin D. Roosevelt said he didn’t even consider the affiliation, because “a man’s private life is supposed to be his private life.”

In 1987, U.S. Court of Appeals Judge Douglas Ginsburg was forced to withdraw his nomination because he admitted to smoking marijuana occasionally during his days as a law student and for a period after graduation.

If either of those nominations were made today, I’d bet the house on getting the opposite outcome.

That’s how it goes. These people are appointed for life to resolve our most difficult disputes in ways that many of us won’t like but will still have to live with. Their values show up in their work, and we want them to represent our values. It’s the least democratic part of our democracy, but the people still want to be heard when these vacancies are filled.

Even before Christine Blasey Ford publicly accused Brett Kavanaugh of sexually assaulting her when they were both teenagers, we have been deluged with letters to the editor and reader-submitted columns about Kavanaugh and why he should or shouldn’t join the Supreme Court (mostly from people who said he shouldn’t). Sen. Susan Collins said in July that she has not been hearing about Kavanaugh from constituents with the same intensity that she felt during the health care repeal battle last summer, but that hasn’t been true here.

We’ve been getting mail in volume that I would expect to see during a presidential election, or a national emergency. The intensity reminds me of the run-up to the Iraq War.

Some of these communications are generated by interest groups like Planned Parenthood, but as much as they would like to have the ability, they can’t turn on the taps and create this kind of outpouring just because they want to. There is an organic concern about Kavanaugh based on what he has said and done as a political operative and a federal judge. Many are concerned that he would roll back women’s reproductive rights and join the four anti-abortion justices now on the court to make legal abortions hard to get, if they can’t make them illegal altogether.

And there is also a question about trust. Kavanaugh, who has written that presidents shouldn’t be subject to criminal investigations while in office, was nominated by a president who is under criminal investigation. His name came off a list provided by the Federalist Society, a private organization that’s funded by some of the country’s wealthiest families, whose main interest is in rolling back regulations that protect the public. And Senate Republicans rushed to get him confirmed when only 10 percent of the documents related to his government work were available. Meanwhile, the nominee danced around questions of substance during three days of empty hearings.

Until last week, none of that seemed to be disqualifying, because Republicans have the votes to push Kavanaugh’s nomination through, on a party-line vote if necessary.

But then this nomination moved from ugly partisan jockeying to one of those foundational debates about what kind of country we are. And while the Constitution is terrific, it doesn’t give us a rulebook for how that’s supposed to work. The most recent example, the Clarence Thomas-Anita Hill hearings in 1991, offer a good guide of what not to do. Hill was cross-examined like a witness in a criminal trial, and Thomas was allowed to make speeches like a candidate for office.

If Ford and Kavanaugh testify this week, we all need to remember that it won’t be in a court of law. There is no presumption of innocence, and there won’t be a verdict. We will all have to judge whether it’s more likely than not this assault took place.

After all we have learned from the #MeToo movement about the prevalence of sexual misconduct, what should we do about a credible allegation of sexual assault? Is it “a man’s private life,” like KKK membership was in the 1930s? Is it less important than recent performance, like marijuana use might be viewed today?

These are the kind of questions senators should be asking instead of looking for ways to minimize what Kavanaugh might have done, or blaming Ford for not coming forward sooner.

The ultimate judgment is history’s. If this man is elevated to our highest court, what will it say about us?