A Catholic school gets to decide if its principal is Catholic enough, the 2nd US Circuit Court of Appeals ruled this week.

The ruling upheld a lower-court finding that Joanne Fratello had no right to sue for discrimination when the Archdiocese of New York declined to renew her contract as principal of St. Anthony School in 2011.

The public-interest law firm Becket, which argued the case for the Archdiocese, had also won the 2012 US Supreme Court decision that served as precedent by protecting a Lutheran school’s similar rights.

At issue was the “ministerial exception,” which allows religious institutions to discriminate on the basis of religion — that is, to require those with religious-leadership roles to effectively advance the relevant faith.

That, the court found, plainly covers the job of a St. Anthony principal, who is expected to lead students in daily prayer and host them at religious ceremonies and to ensure that the curriculum and teachers express Catholic faith.

And, under the ministerial exception, no one except the religious institution itself has any right to decide whether a given individual meets its own religious tests.

Call it a win not just for religious liberty, but for common sense.