Queries about an official’s faith have been answered before—by JFK and others.

An old argument about religion and law has become a political flashpoint. Two decades ago, John Garvey, then a law professor at Notre Dame and now president of Catholic University, wrote an article with a third-year law student on the topic of “Catholic Judges in Capital Cases.” They argued that in some rare but important cases, judges may face an unresolvable clash between the requirements of civil law and the demands of conscience—for example, if called upon to participate in administering the death penalty. The question was what to do. Catholic judges cannot allow their faith to override the oath they took to administer the civil law. Neither can they silence the demands of conscience. The only acceptable course, the authors contended, would be for Catholic judges to recuse themselves from the proceedings. The article’s second author, that third-year law student, was Amy Coney Barrett. Today she is a respected professor at Notre Dame, and President Trump has nominated her to the Seventh U.S. Circuit Court of Appeals. Predictably, this previously obscure article on Catholic judges has been pulled into the never-ending contest over the composition and conduct of the federal judiciary. During Ms. Barrett’s confirmation hearing earlier this month, California Sen. Dianne Feinstein said that “dogma and law are two different things” and told the nominee that “dogma lives loudly within you.” The suggestion that Catholics who embrace the teachings of their church cannot honor their judicial oaths drew a pained response from the Rev. John Jenkins, president of Notre Dame. “I am one in whose heart ‘dogma lives loudly,’ ” he said, “as it has for centuries in the lives of many Americans, some of whom have given their lives in service to this nation.”

During his 1957 Supreme Court confirmation hearing, the Catholic judge William J. Brennan Jr. was asked whether his faith might prevent him from abiding by his judicial oath. “There isn’t any obligation of our faith superior to that,” he replied. Only the Constitution and the laws of the United States would control his conduct as a jurist. Another well-known Catholic justice, Antonin Scalia, did agree with Madison. But unlike Mr. Garvey and Ms. Barrett, he did not believe that the Church’s opposition to the death penalty was firm enough to generate a quandary for Catholics on the bench. Nonetheless, he did not evade the underlying issue: “The choice for the judge who believes the death penalty to be immoral is resignation.” This was also the position of our first Catholic president. In his famous address to the Houston ministers during his 1960 campaign, John F. Kennedy declared that if the time should ever come “when my office would require me to either violate my conscience or violate the national interest, then I would resign the office; and I hope any conscientious public servant would do the same.” New York Gov. Mario Cuomo took a different tack, appealing to what he termed “the American-Catholic tradition of political realism.” In a 1984 lecture at Notre Dame, he asserted that “there is no church teaching that mandates the best political course for making our belief everyone’s rule.” Instead Catholics in public life must endeavor to make practical judgments that are at once “moral and prudential.” None of these Catholics in public life took the position that he had the right to use his office to impose his faith on others. Ms. Barrett doesn’t either. She stated repeatedly during her Senate hearing that it is “never appropriate” to do so and that her religious affiliation and beliefs “would not bear on the discharge of my duties as a judge.” But instead of giving priority to civil law, as Justice Brennan did, or insisting that resignation is the only way to resolve a conflict of conscience, as Justice Scalia did, her law-review article recommended something else: recusal on a case-by-case basis. This was what she and Mr. Garvey believed to be the best way of ensuring that Catholic judges neither betray their conscience nor impose its duties on fellow citizens. Whatever its merits, this stance fits squarely within America’s judicial tradition—and it has nothing to do with dogma.

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