This is what I assumed. He is inferring this idea from a few papal decrees, which is understandable because they usually talk about heretics being against God, but theologians do not make this dinstinction.
I had never heard of the Pius X and XII decrees until Fr Chazal mentioned them. They are VERY important to the discussion. If these popes foresaw the coming catastrophe (and they would be in the best position to see it, because they know who in Rome was orthodox or not) then their decisions are a testament that, even in the midst of a monsterous storm, God's Divine Providence is always prepared and planning ahead.
Yes, because Pope Pius X and XII never actually gave their reasoning for including excommunicated cardinals in the conclave, we can only guess their reasons behind it, but they clearly did not exclude any cardinal whatsoever. The fact is, both popes Pius X and XII made it a requirement, iow, it was not a suggestion or an option - every cardinal that was capable of voting HAD to be part of the conclave and HAD vote, without regard to any censures they might be under, or suspected of, or falsely accused of being under at the time.
I hadn't considered it before but I really like the possible reason that Fr. Chazal's gave betterthan mine, here is another possible reason to consider that
I wrote here:St. Pius X in 1904 said:
“None of the Cardinals may be in any way excluded from the active or passive election of the Sovereign Pontiff under pretext or by reason of any excommunication, suspension, interdict or other ecclesiastical impediment”
Pius XII in 1945 said:
“None of the Cardinals may, by pretext or reason of any excommunication, suspension, or interdict whatsoever, or of any other ecclesiastical impediment, be excluded from the active and passive election of the Supreme Pontiff” (Vacantis Apostolicae Sedis, 1945).
"....it is the popes who appoints or creates the cardinals. Presumably the popes appoint only cardinals they trust, those who are strong in the faith and who are the accusers of heretics, not themselves heretics. They only appoint cardinals they trust will vote the right candidate into office.
If you look at it from pope Pius X and XII's point of view, it actually makes more sense for popes Pius X and XII to make the conclave all inclusive regardless of the cardinal's presumed censure, so as to ensure that the cardinals they appointed will out number or have majority vote or in some way sway the votes in the election of his predecessor, thus helping to insure that the next pope is a good one, even if there are heretical cardinals casting votes in the conclave.
Comparing cuм ex with the new rules, it's as though Pope Paul IV did not trust his cardinals to be faithful, whereas Pius X and XII trusted and depended on their cardinals."
Either way, the law is the law and the popes made a law that apparently, actually risked voting a heretic into the office of the papacy.