A person who procures a completed abortion incurs a latae sententiae [automatic] excommunication.
When it comes to the Catholic politicians that legalize abortion, the proper canon is 915:
Those who have been excommunicated or interdicted after the imposition or declaration of the penalty and others obstinately persevering in manifest grave sin are not to be admitted to holy communion.
In most cases, the individual is told by the bishop not to present themselves for Communion and the appropriate pastors are notified. Usually this is done privately. In rare cases (e.g. Sibelius, during the Obama administration), this is made public.
So, the attacks on the Cardinal Dolan were doubly wrong. First, because they demanded action from someone who could not perform it. Second, the action demanded was not the action that the Church applies. All excommunications involve grave sin, but not all grave sins have the penalty of excommunication. The bishops cannot arbitrarily go beyond the penalty set. This is a safeguard against abuse of power. Otherwise a bishop could excommunicate someone for any minor irritation.
This incident is an example of one problem in the Church. Many people do not know how the Church governs herself. The Church is not a tyranny (rule by the whim of one with dictatorial powers). She is governed by canon law which lists rights, responsibilities, and procedures. The Pope can amend canon law when needed (it is a human law, after all) to serve justice, but he doesn’t do so arbitrarily.
So, it is unreasonable for a Catholic to get angry with a bishop when the bishop doesn’t have the authority to do something through jurisdiction or the obligations of law.
So, the Catholic must ask whether he or she understands how the Church handles things in general and whether he or she has all the information needed to correctly judge what is going on. If the Catholic does not, he or she has no right to condemn the bishop.
If, however, a Catholic should do the required study, and remain concerned that wrong is being done, he or she has an obligation to convey that concern properly. As Canon 212 §3 puts it:
According to the knowledge, competence, and prestige which they possess, they have the right and even at times the duty to manifest to the sacred pastors their opinion on matters which pertain to the good of the Church and to make their opinion known to the rest of the Christian faithful, without prejudice to the integrity of faith and morals, with reverence toward their pastors, and attentive to common advantage and the dignity of persons.
Even if you’re concerned that a bishop made a “bad call,” you have the obligation to be reverent and respectful. That means no snide comments about “backbone” or insults. The bishops are successors to the Apostles and must be treated as such.
This is an example of why the adage, “a little knowledge is dangerous,” is true. A person ignorant of what the Church requires, accusing the Pope or bishop of doing wrong, is risking committing schismatic or heretical behavior because they don’t understand the responsibility and obligations of their office. They are effectively picking a needless “hill to die on.”
Understanding what the Church does and why is essential for assessing the actions of the Pope and bishops. Without that knowledge, those clamoring for “justice” are merely committing rash judgment.