It’s not really true that they have no ethics though, if it was, it’d be a simpler problem, because they’d presumably just care about reducing unpleasant consequences to themselves and as such a legal deterrent should be effective. The issue is that they have different ethics, which are misaligned with everyone else’s and so result in conflict when they stubbornly refuse to do something that everyone else perceives as a no-brainer. It isn’t like the church gets some material gain out of keeping confession secret.