U.S. Sen. Dianne Feinstein again is coming awfully close to expressing anti-Catholic bigotry and close to imposing an unconstitutional "religious test" upon federal judges. Outrageously, several fellow Democrats on the Senate Judiciary Committee are following her lead.

In a committee hearing Wednesday on the nomination of Notre Dame Law School Professor Amy Coney Barrett for a spot on the U.S. 7th Circuit Court of Appeals, Feinstein and her Democratic colleagues pelted Barrett with questions about her Catholic faith and its relation to duties as a federal judge.

"When you read your speeches, the conclusion one draws is that the dogma lives loudly within you," said Feinstein of California, the committee's ranking Democrat. "And that's of concern when you come to big issues that large numbers of people have fought for, for years in this country."

The dogma lives loudly within you. Really? Is that some sort of all-too-clever reverse-Star Wars-allusion?

To be clear here, the charge is that Barrett is an observant, perhaps even traditionalist, Catholic. So what? And why, pray tell, should that be "of concern" with regard to a federal judgeship? All our judges who happen to be Catholic should be good and faithful Catholics and our Jewish judges faithful Jews and Hindu judges faithful Hindus. The more they adhere to the terms of their faith, the more we can trust that their character is strong and solid – and that therefore they will abide just as assiduously to their oaths of civil office.

Feinstein doesn't seem to think so. She thinks that a faithful person, especially a faithful Catholic, is automatically suspect. This isn't the first time.

Fourteen years ago, Feinstein, along with now-Senate Minority Leader Chuck Schumer and now-Whip Richard Durbin, led the charge against William Pryor, who was being nominated for the spot on the 11th U.S. Circuit Court of Appeals. (Pryor eventually was confirmed and still holds the seat.) Schumer repeatedly questioned Pryor's "deeply held beliefs" – specifically, his Catholic beliefs – while Feinstein disapprovingly quoted, out of context, a line from a commencement speech Pryor had made for his alma mater, the McGill-Toolen Catholic high school in Mobile.

Pryor had said that "the challenge of the next millennium will be to preserve the American experiment by restoring its Christian perspective," and Feinstein had countered that such a statement somehow violated the nation's supposed "absolute separation of church and state."

As I explained back then, Feinstein had been objecting to a speech in which Pryor was approvingly quoting St. Thomas Aquinas and theologian John Courtney Murray. Rather than advocating a subjugation of civil law to church "dogma" (to use Feinstein's term), Aquinas had been arguing that good Catholics must be better citizens. Murray, in turn, had been asserting that Catholics should be good citizens of the United States specifically, as a pluralistic society dedicated to the ideals of the Declaration of Independence.

What I wrote then applies now, in light of the Feinstein-Durbin verbal assault on Professor Barrett: "Sens. Feinstein and Durbin might have a hard time explaining to the nation's 64 million Catholics how it disqualifies a man from a judgeship if he quotes from St. Thomas Aquinas."

So outlandish was the Democratic assault back then that a conservative group ran ads accusing Democrats of saying "Catholics need not apply." Feinstein and her Democratic colleagues freaked out – but the freakout was an example that the truth hurts. Feinstein keeps forgetting the lesson. Since then, she occasionally has returned to the same stance, even asking John Roberts, when considering his nomination as Chief Justice, if he would "address the issues of conscience out of a focus on the national interests, not out of adherence to the dictates of [your] religion."

In the case of Professor Barrett, the whole foofaraw arises out of an essay she co-wrote (as the junior partner) two whole decades ago, as a law student, saying that under certain very limited circumstances a Catholic judge might need to recuse himself from issuing an order to execute a convict. Not a thing in the essay is outlandish.

Barrett has sterling qualifications for the bench. She was a Phi Beta Kappa graduate of Rhodes College, summa cum laude with multiple awards from Notre Dame, a clerk for the late Supreme Court Justice Antonin Scalia, and an associate at a top law firm before becoming a leading law professor.

The bigger question isn't whether this distinguished professor doesn't understand what her judicial oath requires, but rather whether Feinstein understands, as Nebraska's Sen. Ben Sasse noted, that it is unlawful to impose a religious test on public officials.

The real danger to our constitutional system comes not from Amy Barrett's Catholicism, but from Feinstein's animus against it.

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