Liberals in the Catholic Church are a sensitive bunch. Not sensitive to others, of course, but to themselves and their friends. If they see another liberal disciplined, they always defend him, even if (like the former Bishop of Toowoomba in Australia) they would hesitate to agree with what he said. Such disciplinings are extremely rare, but acts of Papal authority are becoming a little more forthright under the present Pope (and God be thanked for that), and the liberals have an increasingly long list of things they disagree with which are actually going to be enforced. They are being compelled to accept things which they can't prevent, such as the Anglican Ordinariate and celebrations of the Traditional Mass; they are being asked to do what they do not want to do, such as use the new Missal translation; and they are being told not to say things they want to say, such as that women can be ordained priests.
I have no doubt at all about the sincerity of Catholic liberals, so the question arises whether their refusal to obey - should they refuse - would be morally justifiable. After all, the Church teaches that we should follow our consciences. Actually, this is almost a truism, since your conscience is that faculty which tells you what you are obliged to do: it would be nonsense to say 'you ought to do what you believe you ought not to do'. So if a liberal Catholic thinks it would be wrong not to be as obstructive as possible to those who want a Traditional Mass, to use the new Missal translation, or to remain silent about the ordination of women, what should they, in conscience do? What would it be reasonable for their superiors to punish them for? And in doing what would they be committing a sin?
A full treatment of this would require a book; I'm just going to make a few points. First, a knee-jerk Ultramontanism which says that you should do whatever you are told by a legitimate authority is wrong. This is called 'Indiscreet Obedience' by St Thomas Aquinas and is a serious error. If you are told to commit a sin, you must not do it, nor do you avoid committing a sin yourself by the plea that you were commanded to do it. The command is no defence because even if the person commanding has legitimate authority that authority does not extend to commanding sins. You are no more obliged to obey the Pope if he tells you to commit fornication than you are obliged to obey a car park attendant if he tells you to hang blue curtains in your living room.
Second, Catholic traditionalists do not find knee-jerk Ultramontanism at all attractive, because although we'd all like to see liberal excesses curbed, we can see what damage this 'I was only obeying orders' mentality did to the Church in the 1960s and 1970s. A large percentage of a generation of priests who were brought up on obedience and (apparently) little else wrecked their churches and drove countless souls out of the practice of the Faith by zealous application of ill-considered initiatives deriving from what they took to be legitimage authority. On closer inspection many of the things encouraged by bishops or Diocesan liturgical directors and the like were contrary to authoritative documents from Rome, but these priests didn't see it as their place to question such things. When asked they would often say that it wasn't their idea, they quite liked the old high altar, the Penny Catechism or whatever it was but they had to obey. This was obedience in wilful ignorance of the rightness or real bindingness of the command.
So not only must you not obey what you know to be a sinful command, but you cannot close your eyes to the possibility that it is sinful and hope for the best. Does that mean Catholics, even those with special vows of obedience, should only obey commands they happen to agree with?
That would appear to be the position of many liberals. Documents from Rome which they don't like go into the wastepaper basket regardless of their level of authority, unless they tickle the recipient's fancy. This is the opposite extreme to what I've called knee-jerk Ultramontanism and is also wrong. The correct position depends on an understanding of what authority in the Church is actually for.
Authority in the Church, like authority in the family and the state, is for the promotion of the Common Good. In the Church this is specifically the good of souls. Commands which are contrary to the good of souls have no binding force, because they are failures as commands, in the same way that they would be failures if they were not promulgated, or asked you to do something yesterday, or to breath underwater. This is recognised explicitly in the canon law tradition, which says 'the good of souls is the supreme law'. The Church operates with a Natural Law understanding of law, not a Legal Positivist conception.
Since it is the precise role of people in authority to determine what is for the good of souls in particular concrete circumstances, those commanded don't need to second-guess them all the time. We can give them the benefit of the doubt when commanded to do something we don't fully understand. It is only when it is clearly contrary to the good of souls that this principle comes into play.
Now the liberals may think this gets them off the hook, since they think it is clear enough, but in considering what is for the good of souls we are not starting with a blank piece of paper. Scripture, Tradition, the constant practice of the Church, the Magisterium, the Sacraments: these things teach us what is for the good of souls. Being formed by these things in one's moral understanding is to have a 'formed conscience': the kind of conscience which is not just willfulness, but that we really should obey.
And this is the key to the error of many 'conservative' Catholics who over the years have attacked Traditionalists and said that we are no better than liberals in subjecting Church documents to examination and criticism and not just blindly obeying everything. Because if you have a formed conscience, if you are properly formed in the Church's Tradition, in scripture, in the Magisterium, then you will have more reason to disobey commands (or purported commands) which are contrary to Tradition, Scripture, and the Magisterium, and less reason to disobey commands which protect, advance, and reiterate what is found in Tradition and so on. So far from the Traditionalist and the liberal being parallel in disobedience, they are taking opposite positions.
The liberal may argue that the new Missal translation, for example, is not for the good of souls, and I grant he may really believe that. But look at the arguments and it quickly turns out that what he doesn't like is in many cases simply the accurate rendering of liturgical texts which are deeply embedded in the Church's tradition. Catholics have always (since at least Pope Gelasius) said Christ's blood was shed 'pro multis': to say it is wrong to say it was shed 'for many' is to reject the constant teaching of the Church.* To say that it is not for the good of souls that they be exposed to the teaching of the Church is to cease to be Catholic. (We're not talking here of some situation under persecution where explaining the subtleties would be impossible, where the Church's enemies will seize on some formulation to damage the Church, or anything like that.)
Similarly, when liberals disobey liturgical law, the laws they disobey are attempts to keep them in line with tradition. In using General Absolution, pottery chalices, leaving the sanctuary to give the kiss of peace, etc. ad nauseam, they may think they act for the good of souls but they are rejecting the guidance of the Church herself on what is good for souls - not just the views of the jack-in-office (if there is one) seeking to enforce the petty rule, but the voice of Christ speaking through the Church's immemorial traditions, discipline, and Magisterium.
We are beginning to see more traditionally-minded priests bending some of the rules of the Novus Ordo to make it more traditional. The Holy Father does this from time to time. I won't go into details, but we are talking about minor rubrical issues. Cardinal Burke, the Church's chief legal officer under the Pope, has been criticised for wearing a galero. Are the Holy Father and Cardinal Burke undermining a proper respect for the Church's law? No. Sure, these things are not explicitly permitted in the latest edition of the rule book. But breaking rules in this way is NOT parallel to the liberal breaking of rules, since it is in accord with tradition, not against it. The Church tells us that certain rubrical gestures are helpful to the faithful and pleasing to God: the Church tells us that when we read that they were used by the Church for a millennium or so. If they can be used once more in the Novus Ordo when not explicitly called for in the current rubrics, without causing 'admiratio', well it is not for me to give permission for this kind of thing but I'm not going to complain either. What it is not is a parallel to a liberal priest doing what has been deliberately rejected by the Church for a millennium or so and is still contrary to the rules, because the Church in her wisdom judges it harmful for souls.
The liberal may appeal to conscience, but where does this conscience come from? If the liberal's conscience is not 'formed', it is not Catholic, it is just willfulness. If the liberal's conscience is not Catholic, the Church needs to use her discipline to protect the faithful and perhaps even to convert the liberal.
*In response to criticism my reasoning here is as follows. 'Pro multis' is the teaching of the Church; 'for many' is simply an accurate rendering of that phrase; to reject 'for many' is ipso facto to reject 'pro multis', and therefore to reject the teaching of the Church. The case I have in mind is where, as noted earlier, "it quickly turns out that what he doesn't like is in many cases simply the accurate rendering of liturgical texts". The reasoning of many liberal dissenters appears to be against not so much 'for many' as a translation of 'pro multis' but 'pro multis' itself. I say 'appears' and it is not my purpose to pick out named examples of people who hold the view, but only to ask what someone who did in fact hold such a view would be morally obliged to do about it.