EWTN Catholic Q&A
Question from c mcshea on 04-19-2005:

Did John Paul II ever excommunicate anyone? Were Lefebvre and his gang actually excommunicated?

Answer by Colin B. Donovan, STL on 05-04-2005:

More often than not people are excommunicated by the law itself: for heresy, apostasy or schism, for direct procurement of abortion, for violating the seal of confession etc... When they knowingly and willingly do something for which they know they can be excommunicated, in that instant they are automatically excommunicated. So, every time a Catholic incurred such excommunication, it could be said that Pope John Paul excommunicated him or her, as the law works by virtue of papal authority. The numbers of such unknown excommunications could be in the thousands, even millions, especially given the vociferous dissent from defined Church teaching in some parts of the world. Likewise, schism, and apostasy from Christ (in favor of new age and other religions) could be in very large numbers. We simply don't know. Such people may go to Mass, and for most observers be seemingly "good Catholics."

Excommunication can also be declared, that is, a bishop, or the pope, after an investigation makes a public declaration of excommunication. Archbishop Lefebvre, his co-consecrator, and the four SSPX bishops they consecrated, are such declared excommunicants. They were excommunicated immediately b yteh law, but to make sure everyone udnerstood, they were also declared excommunicants, along with anyone (priests or laity) who adhered to their schism. In the case of priest members of the SSPX this adherenece is reasonably assumed; in the case of the laity, it is more difficult to assume (as their motives may simply be a preference for the former Mass, and not rejection of papal authority in the matter.)

The Holy See has also excommunicated others, including 6 women who attempted to be ordained priests, and a theologian, later reconciled. Clearly, however, the number of the "hidden" excommunicants far exceeds the declared ones, in John Paul's or any pope's pontificate.