This question is, oftentimes, raised regarding several “hot button” moral issues including abortion, gay marriage, war, euthanasia, stem cell research, etc. The classic example of this is a politician who claims to have a well-formed conscience who is told by his bishop that he cannot receive Holy Communion because he legislates contrary to a church teaching. Is the church trying to impair the politician from freely doing his job? Is the bishop justified in stating that the politician’s actions have excommunicated him? The easy answer to both questions is: It depends. The difficulty comes in defining on what circumstances it depends.
First off, I feel like I need to clarify a few terms. What do we mean by “informed conscience”? One can find a great definition of a conscience in the Catechism of the Catholic Church #’s 1776-1802. To abbreviate the content of those paragraphs, the conscience is “present at the heart of a person” to help guide a person in making moral decisions. Without the conscience, a person would not be culpable for his or her actions because it would be impossible to know right from wrong. A person spends a lifetime forming his or her conscience. The Word of God is key to the formation of conscience, though the church does not restrict the Word of God to just the Bible. The Bible is part of the larger Word of God but, ultimately, “We are assisted by the gifts of the Holy Spirit, aided by the witness or advice of others and guided by the authoritative teaching of the Church.”
So, in some ways, a fully formed conscience could not be in conflict with church teaching on issues on which the church has definitively decided, since it is what guides the formation of conscience. There are times in which a person, through no fault of his or her own, may not have a fully formed conscience. If the person was incapable, at the time of occurrence, of knowing what the teaching of the church was, they cannot be held accountable. Also, related to this, there is the prospect that a person is in the process of growing deeper in his or her understanding and is simply not to the point of learning (let alone accepting) a church teaching. In those cases, it’s possible that someone hasn’t yet had the church’s teaching on same-sex marriage or euthanasia explained to them or may have had an inadequate explanation. The person has an informed conscience but is ignorant of church teaching. Of course, it is the responsibility of the individual to seek out the full explanation of church teaching and not simply rely on ignorance as a rationale for not obeying the church.
Having said all of the above, there is room for legitimate disagreement with church authority if the church has not definitively stated a position on something or if the application of moral principles in a given situation is not entirely clear. For example, it is not legitimate to say that you wholesale disagree with the church’s teaching on abortion but are still a catholic in good standing. The church has been consistently clear that abortion violates the law of love and the dignity of the human person. But, if a pregnant woman has uterine cancer and would die without removing it, there is room for legitimate moral disagreement. Some moral theologians say that you are justified in removing the cancerous uterus since you are preserving the life of the mother and not intending on committing an abortion. Others disagree and say abortion is, nonetheless, an indirect result of the action and, therefore, it should not be taken. Oftentimes, the application of moral principles in complex situations is where moral theologians will disagree.
To know if something has been definitively decided, one should look toward the Catechism of the Catholic Church and official church statements. And, remember, not every statement that a priest, bishop or educated lay person makes is definitive. As a priest, I can tell you that I have very often been saddened by priests who either are unwilling to teach what the church teaches on tough moral teachings or who seem to believe that every statement they make is definitive.