About Biden, let's ask the right questions well
Sen. Joseph Biden, a left-of-center politician who generally earns high marks from liberal watchdog groups, is not the extremist that Sen. Barack Obama is proving to be, and he has incomparably more experience in government than does Obama. But, while Biden's positions on public policy issues can and will be attacked and defended by Catholics (particularly, I hope, by informed lay Catholics whose expertise is the temporal order as recognized by 1983 CIC 225.2 and 227), Biden-qua-politician should not be the object of special attention by ecclesiastical leadership. Rather, Biden-qua-Catholic should be. And he will be.
Canon 916 directs Catholics who are conscious of being in grave sin, regardless of whether that grave sin is known publicly, to refrain from taking holy Communion. Biden, like any other Catholic, is expected to examine his conscience in light of Church teaching prior to approaching the Eucharist and, if he finds himself wanting, to reform his behavior accordingly. He can be sure that the grace of Christ would be offered abundantly to him in that effort.
But Canon 915 looks at a different issue. Unlike Canon 916 which impacts individual Catholics, Canon 915 directs ministers of holy Communion to withhold the Eucharist from Catholics "obstinately persevering in manifest grave sin".
Any Catholic whose public behavior, in one or more respects, is so at odds with Catholic moral teaching(s) as to constitute his or her "obstinately persevering in manifest grave sin", is subject to consequences under Canon 915. There's no fine-print exception for Catholic politicians. Biden-qua-Catholic is subject to the same rules as is every other Catholic.
To be sure, the public profile of Catholics in political office is considerably higher than that of ordinary Catholics; consequently their actions will receive closer attention than that accorded to pew Catholics. But so what? Citizens aspiring to major public office are subject to markedly higher scrutiny under civil law, and few have a problem with that. Should Catholics seeking a major role in the service of the common good suddenly be allowed to claim immunity from their responsibility as Catholics "to imbue and perfect the temporal order of things with the spirit of the Gospel"? I think not.
In regard to the Catholic Joseph Biden's eligibility to receive holy Communion, then, the right questions will seek to answer whether certain of his public actions (chiefly legislative actions and public advocacy efforts) constitute obstinate perseverance in manifest grave sin. Answering those questions well will require (1) accurate assemblage of the facts (an area for which expert lay Catholic observers of American politics should be consulted), and (2) accurate inquiry into the requirements of Church law and moral teaching (an area for which bishops are chiefly responsible).
Here's hoping that the right questions in this important matter are asked well.