Bellarmine on Extraordinary Papal Elections
Bellarmine's Controversies, De clericis, bk. I, ch. 10. (Translated by James Larrabee, with comments)
If there were no papal constitution on the election of the Supreme Pontiff; or if by some chance all the electors designated by law, that is, all the Cardinals, perished simultaneously, the right of election would pertain to the neighboring bishops and the Roman clergy, but with some dependence on a general council of bishops.
In this proposition, there does not appear to be universal agreement. Some think that, exclusive of positive law, the right of election would devolve on a Council of Bishops, as Cajetan, tract. De Potestate Papae & Concilii, cap. 13 & 21 & Francis Victoria, relect. 2. quest. 2. De potestate Ecclesiae. Others, as Sylvester relates s.v. Excommunicatio, 9. sec. 3, teach that in that case the right of election pertains to the Roman clergy. But these two opinions can be reconciled. Without a doubt, the primary authority of election in that case pertains to a Council of Bishops; since, when the Pontiff dies, there is no higher authority in the Church than that of a general Council: and if the Pontiff were not the Bishop of Rome, or any other particular place, but only the general Pastor of the whole Church, it would pertain to the Bishops either to elect his successor, or to designate the electors: nevertheless, after the Pontificate of the world was joined to the bishopric of the City [posteaquam unitus est Pontificatus orbis Episcopatui Urbis], the immediate authority of electing in that case would have to be permitted by the bishops of the whole world to the neighboring bishops, and to the clerics of the Roman Church, which is proved in two ways.
First, because the right of election was transferred from all the neighboring bishops and the Roman clergy to the Cardinals, who are a certain part of the bishops and clergy of the Roman Church; therefore, when the Cardinals are lacking, the right of election ought to return to all the bishops and clergy of the Roman Church.
Second, because this is a most ancient custom (as we showed above from Cyprian), that the neighboring bishops, in the presence of the clergy, should elect both the Bishop of Rome and others also. And it is unheard of that the Bishops or Archbishops of the whole world should meet for the election of the Supreme Pontiff, except in a case where it is doubtful who should be the legitimate electors. For this doubt ought to be resolved by a general Council, as was done in the Council of Constance. [This is the entire text of chap. 10.]
It should be noted that in this book, St. Robert treats first of the election of bishops, refuting the Protestant theory of popular election (revived by modern liberal "Catholics") at considerable length (chap. 7). He then deals in detail with the election of the Supreme Pontiff (chap. 9). The proposition at the head of chapter 7 reads: "The right of electing the Supreme Pontiff, and the other Pastors and Ministers of the Church, does not belong to the people by divine right. But if, at any time, the people had any power in this matter, that was entirely from the connivance or the concession of the Pontiffs."
Another point to keep in mind in this context is that the neighboring bishops to the see of Rome are actually the Cardinal Bishops, the bishops of the suburbicarian sees. These have been associated in the government of the Church by the Popes from the earliest times. On this Bellarmine says in chap. 9 (in which he is concerned to show that the constituted method of papal election by the Cardinals, while not of divine law, is the best and should be retained): "The second manner [of electing a Bishop] was, that all the Bishops of the same province, or the majority of them, should elect the Bishop, after, however, requesting the testimony and consent of the Clergy and people of the place to which the Bishop is being given: and in the same manner were elected Metropolitans, Patriarchs, and the Supreme Pontiff himself, namely by the neighboring or provincial Bishops. And this was the most ancient manner ..." Further down he says: "The second manner is found in this form [of papal election, that is, election by the Cardinals], insofar as the principle element in it is concerned; for the neighboring Bishops now elect as they then elected, namely the six Cardinal Bishops."