My friend and Canon Lawyer Ed Peters writes,
A note on proposals to require priests to violate the seal of confession
Concerning recent Irish and Australian proposals to require priests who, through their ministry in sacramental confession, learn the identity of child sexual abusers (or of any other malefactors, for that matter), to disclose such information to civil authorities, I have little to say because, well, because there is little to say, canonically, at any rate. Such proposals, even if they become law, will have absolutely no effect on a priest’s obligation to preserve the seal of confession. Absolutely none.
The seal of confession is a not creature of civil law, rather, it rests on divine law and is articulated by canon law (see cc. 983 and 1388). Because the state has no authority over the seal of confession, it can exercise no authority over the seal by way imposing, regulating, or revoking it, in whole or even in part.
What states can do, and indeed what enlightened states in fact do, is to accommodate the seal of confession within theirs laws (typically, in their laws of criminal evidence procedure). The benefits to states making such accommodations are many, and the “benefits” of disregarding the seal can be shown, upon a few moments’ consideration, to be nugatory, but such prudential points are better made by others. I speak only as a canonist, and I write only to say that any civil laws attempting to break the seal of confession would have no force whatsoever against the sanctity of the seal of confession.
By the way, the picture to the right is of Montgomery Clift playing a priest in Alfred Hitchcock’s “I Confess” (visit the link and watch the trailer). It is a thriller but also a profound statement on the seal of confession adn the nobility of the priesthood. If you haven’t watched it, or it has been a while — get the family together with popcorn, some Kleenex and be again proud to be Catholic.