“The dogma lives loudly within you,” Feinstein said. “And that’s of concern when you come to big issues that large numbers of people have fought for for years in this country.”

While recent Senate hearings have skirted the boundary of posing religious tests for public servants, raising constitutional questions, something more complicated seemed to be going on here. Sheldon Whitehouse, the Democratic senator from Rhode Island, expressed frustration that Barrett and her fellow nominee at the hearing, Michigan Supreme Court Justice Joan Larsen, refused to discuss how their personal beliefs might shape their legal thinking. He and the other Democratic senators seemed to believe that religious convictions affect how judges apply the law. “To sit here and pretend that there is no role for people’s personal and private views … when they go to the court—it’s just, it’s so preposterous as to be silly,” Whitehouse said.

As conservative, often religiously motivated positions on issues like gay marriage and banning abortion increasingly become out of step with popular opinion and legal precedent, this boundary between personal conviction and legal fidelity is going to become even tricker to navigate. What’s the line between examining a nominee’s religious convictions and believing those convictions disqualify her from serving the country?

Democratic senators cited a number of concerns with Barrett’s past statements and writings. But by far, they spent most of their time questioning a 1998 paper Barrett wrote as a law student along with John Garvey, who is now president of the Catholic University of America.

In the paper, the two authors explore whether a Catholic judge should recuse herself from death-penalty cases if she would be unable to impartially uphold the law because of her religious convictions. “The pope and the American bishops have recently offered clear and forceful denunciations” of the punishment, they reason, and many Catholics feel morally obligated to uphold the teachings of the Church. In certain, limited circumstances, they argue, federal judges should step back from involvement in cases that might raise conflicts of conscience.

They did not, however, argue that judges should step back from morally complicated cases all, or even most, of the time. “It turns out that the number of cases in which we thought an adherence to your moral principles would prevent you from deciding a case according to the law was much smaller than we imagined,” said Garvey in an interview.