In my opinion, all of the signatories are guilty of public formal schism, and are therefore automatically excommunicated. The Holy See could issue a warning to the signatories to recant, and then issue an excommunication (ferendae sententiae), if they do not. This harsh action seems unlikely under the current Roman Pontiff. But who knows what his successor might do?
Aside from excommunication, what other action might the Church take?
A large number of signatories are priests, two so far are deacons, one so far is a nun, one is a retired Bishop. Some of the lay signatories are professors at Catholic institutions of higher learning, including some Pontifical Universities. The Church possesses the authority to take action against these persons.
Can. 1369 A person who in a public show or speech, in published writing, or in other uses of the instruments of social communication utters blasphemy, gravely injures good morals, expresses insults, or excites hatred or contempt against religion or the Church is to be punished with a just penalty.
The signatories have falsely accused the Roman Pontiff of propagating heresies. Such an accusation injures good morals by scandal, that is, by the bad example of a public sin. The Filial Correction expresses insults and excites contempt against the Church by this false accusation. So Canon 1369 applies, and a just penalty can be issued.
The supporters of the Filial Correction will argue that the Pope is guilty of propagating heresies, and so their correction, being supposedly filial, does not injury good morals, or express insults, or excite contempt. But if the Holy See or any Bishop or Conference finds that the Pope is not guilty of this accusation, the Canon would apply.
Can. 1373 A person who publicly incites among subjects animosities or hatred against the Apostolic See or an ordinary because of some act of power or ecclesiastical ministry or provokes subjects to disobey them is to be punished by an interdict or other just penalties.
The signatories are publicly inciting animosities among the subjects of the Roman Pontiff by asking them to sign a document which makes serious accusations against him, and which accuses him of causing grave harm to souls by many different acts of ecclesiastical power or ministry. The document also strongly implies that the subjects of the Roman Pontiff should disobey him in all of these acts and alleged errors. For if a person is accused of propagating heresies, the implication is that the readers are being warned not to assist or cooperate in this grave sin.
The claim that the accusations of the Filial Correction are true does not entirely remove the effect of this Canon, since publicly rebuking the Roman Pontiff and asking people to sign publicly also would have the effect of inciting animosities and disobedience.
Can. 1399 In addition to the cases established here or in other laws, the external violation of a divine or canonical law can be punished by a just penalty only when the special gravity of the violation demands punishment and there is an urgent need to prevent or repair scandals.
The Filial Correction is causing scandal worldwide. The new story has been widely covered, and has reached very many souls. The accusations against the Pope are very grave. And so this Filial Correction and the process of adding more and more signatories creates an urgent need to repair this scandal. Moreover, the Ten Commandments (divine law) include an explicit prohibition against bearing false witness. Publicly signing a false accusation that the Pope is propagating heresies certain violates that commandment: Thou shalt not bear false witness against thy neighbor. And the harm and scandal is greatly increased when the object of the false witness is the Vicar of Christ.
Perhaps you don’t think that Pope Francis, being a liberal Pope who often speaks of mercy, will take any action against the signatories. Do you not remember the action he took against some rebellious priests in Africa? In the dioceses of Ahira, Pope Francis gave the priests there an ultimatum: “Either write to him promising ‘total obedience’ or face suspension.”
Each priest’s letter, he said, “must clearly manifest total obedience to the pope” and indicate a willingness “to accept the bishop whom the pope sends and has appointed.
“The letter must be sent within 30 days, from today to July 9th, 2017. Whoever does not do this will be ipso facto suspended ‘a divinis’ and will lose his current office,” the pope said, according to the posts. [CruxNow.com]
Many people were surprised at this action. But I say that the Roman Pontiff must sometimes issue punishments against disobedient priests, for the good of the Church and the salvation of souls
Pope Francis could also take action against the signatories. Priests and deacons could face suspension or eventually laicization. Religious could be expelled from their order. Professors at Pontifical Universities could be forbidden from teaching the Catholic faith.
It is also possible for Bishops’ Conferences or individual Bishops to take similar action against the signatories.
What if Pope Francis decides not to take any action against the signatories? His successor in the chair of Saint Peter could do so. In fact, a Pope does not need Canon Law in order to take action against priests, deacons, or religious, or lay persons who rebel against his authority or who make accusation against him or against his predecessor. The signatories are opening themselves up to just punishment issued by Pope Francis or his successor, as well as any punishments from their Bishops or Bishops’ Conferences.
Finally, let me point out that signing a document which falsely accuses the Roman Pontiff of propagating heresies and gravely harming souls is an objective mortal sin against God. Two of the four Dubia Cardinals have died and been judged by the Almighty. I would not want to be in their shoes on Judgment Day.
UPDATED with this quote from LifeSiteNews.com
Is there a concern among the signatories — either priests or lay scholars — that they might suffer reprisals?
Yes, there is a concern about that. I have heard from many people in Catholic institutions (here in Santiago and elsewhere) who have been directly threatened with this, and therefore they didn’t sign. For example, I have heard from some people who signed the document of the 45 and they were told not to sign anything else or they would lose their position. Of course, one is more at risk depending on the kind of institution. I have heard of people being threatened, not directly from Rome but by the local institution, sometimes striving to be “more Roman than the Pope.”
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