Lots of controversial cases at the intersection of religion and the law wind up before the Supreme Court.
And, for most of U.S. history, the court, like the country, was dominated by Protestant Christians. But today, it is predominantly Catholic and Jewish.
It has become more conservative and is about to get even more so with President Trump's expected pick to replace Justice Anthony Kennedy, who is stepping down from the court at the end of July.
Everyone on President Trump's shortlist, but one, is Catholic. So what, if anything, do the current justices' and potential nominees' faiths tell us — and how has the religious make up of the Supreme Court changed?
"It's extraordinary and unprecedented in American history," said Louis Michael Seidman, a constitutional law professor at Georgetown University, which is affiliated with the Catholic Church. "There was a time when, for example, there was tremendous anti-Catholic bias ... and, of course, there was a time when there was a lot of anti-Semitism, and a lot of that has gone away."
A majority Catholic court
Today, six of the nine justices are Catholic — if you count Neil Gorsuch, who was raised Catholic and has attended an Episcopal Church. The other three are Jewish.
Trump's potential nominees — Judges Brett Kavanaugh, Amy Coney Barrett, Thomas Hardiman and Amul Thapar — are all Catholic. NPR's Nina Totenberg reports, according the Federalist Society, Judge Raymond Kethledge is evangelical.
Barrett's membership in a conservative religious group became an issue during her confirmation hearing to be an appeals court judge last year.
"When you read your speeches, the conclusion one draws is that the dogma lives loudly within you, and that's of concern," Democratic Sen. Dianne Feinstein of California told Barrett. That prompted a backlash from critics, who accused Feinstein of being anti-Catholic.
It also enamored Barrett, a former Notre Dame law professor, to religious conservatives.
Except Justice Sonia Sotomayor, all of the Catholic justices on the Supreme Court are conservatives, appointed by Republican presidents. And there's reason for that.
While there is a liberal, social-justice strain in Catholicism, there is a sharp divide between those who emphasize that and more conservative Catholics. And their dominance on the court has to do with ideology, said Marci Hamilton, a professor at the University of Pennsylvania who once clerked for former Supreme Court Justice Sandra Day O'Connor.
"I think it's because the Catholic vote can be relatively predictable on abortion," Hamilton said. "Now, that doesn't fit with Justice Sotomayor, but with respect to the male Catholics that have been on the court, they have been largely devoted to decreasing the power of Roe v. Wade."
That's a major goal for many conservatives, and one supported by Catholic theology.
The evangelical anomaly
Kethledge, a judge from Michigan, who wrote a book about the power of solitude, is an anomaly for his evangelicalism — and being on any Supreme Court shortlist.
Despite white evangelicals' strong support of President Trump and their prominence on the political landscape, there isn't a very deep bench of evangelical judges for Trump to draw from.
"It is a bit of a mystery why we have so many Catholics, in an era in which Protestant evangelicals are in such strong political power," Hamilton, the University of Pennsylvania professor, said.
But John Fea, a historian at Messiah College, an evangelical institution also in Pennsylvania, said he thinks the lack of evangelicals on the court, has to do with "the direction that the Evangelical Movement has taken in America."
Unlike Catholicism and Judaism, Fea said, both of which have a long intellectual tradition, American evangelicalism has been more practical in focus.
"Evangelicals are primarily concerned with preaching the gospel, with evangelism, with social justice ministries, service," Fea said. He added, "And they have not always valued the life of the mind. So as a result, you have a lot of evangelicals doing great things, but they're not necessarily pursuing intellectual vocations — the liberal arts, philosophy, logic, history these kinds of things — because they're out trying to win people to Christ."
The law, a refuge for those of the Jewish faith
As for why members of the Jewish faith have been elevated (and all by Democratic presidents), Harvard Law Professor Noah Feldman said it's partially explained by the fact that there's a strong pipeline of Jewish judges and professors.
"The reason for that is also a little hard to pin down," Feldman said, "except to say that academia was an area which, like many other areas of American life, was originally closed to Jews in the late 19th Century."
But Feldman said law schools began opening up to Jewish professors before many other academic disciplines.
Rabbi Evan Moffic, writing in The Huffington Post in 2016 when Merrick Garland, who is also Jewish, was nominated to the court by Barack Obama, argued that history and values account for why so many people of the Jewish faith in America are drawn to the law.
"Until the American Constitution," Moffic writes, "Jews had never experienced equality under the law. We were always tolerated minorities, convenient scapegoats when economic and political times got tough. The founding of America altered this pattern."
As far as values go, Moffic writes:
"The first Jewish leaders were not generals or kings. They were judges. Some have criticized Judaism for being too legalistic. We are seen as a religion of law rather than love. I've always taken that as a compliment rather than a criticism. Love is blind. Love overwhelms reason. Love is one of the greatest gifts God gives us, and we could not survive without it. But love is always particular. We love certain people and things. It cannot serve the foundation of a just nation. For that we need law that treat us equally. Laws allow for equality of opportunity."
None of that means Jewish judges and professors haven't faced — and aren't still facing — discrimination. In 2010, after Elena Kagan was nominated for the court, former Republican and Reform Party presidential candidate Pat Buchanan lamented that there would be too many Jews and no Protestants on the Supreme Court.
And weeks after Trump was elected, a visiting Harvard Law professor, who had written anti-Trump blogs and op-eds, received an anti-Semitic postcard in the mail that closed with: "We're gonna drain the swamp at Harvard Law. Juden Raus!" (Juden Raus translates to "Out with the Jews.")
The lack of Protestants
Mainline Protestants, while dominant for most of American history, are all but absent on the court. Aside from Gorsuch, the last mainline Protestant justice was John Paul Stevens, who retired in 2010.
Anne Marie Lofaso, a professor at West Virginia University College of Law, said she thinks the court has gradually shifted away from Protestant justices in recent years in part out of a push to diversify the court.
"Even though we're not a Christian country in the sense that we have the First Amendment establishment clause," Lofaso said, "we are a country that reflects not just Judeo-Christian ideals, but very much Protestant ideals, more so than any other denomination of Christianity, and more so than any other religion.
"And so, in that sense, it becomes less important, I think, in a country that has been so obsessed lately with diversity, to actually get that [Protestant] voice on the court; it becomes more important to get minority voices."
Feldman, from Harvard Law, said in a perfect world, the justices' religion – or lack of it – wouldn't matter. It would just be about who is a good judge.
"If you think about it, the Constitution itself says there shall be no religious test for office, so it will be good not to think about it in any way," he said. "In reality, of course, there is some broad cultural association sometimes between people's religious beliefs or affiliations and their politics."