Are there any kinds of acts that are absolutely immoral, always, in all circumstances, regardless of good intention?
Yes. These types of acts are called intrinsically evil. Such an act is immoral by its very nature, that is, by its inherent moral meaning. The act is immoral in and of itself, by its essential moral nature.
An intrinsically evil act is not necessarily very immoral, not necessarily a grave or mortal sin. When we say that an act is intrinsically evil, nothing is asserted as to the gravity of the sin — until we know the reason that the act is evil. Some intrinsically evil acts are venial (light) sins, such as a lie about a small matter. Other intrinsically evil acts are mortal (grave) sins, such as murder.
Even with a good intention, and in dire circumstances, the commission of an intrinsically evil acts is objectively a sin. And if that sin is committed as a knowing choice — knowing that the act is immoral, and willingly choosing that act despite that knowledge — then the act is an actual sin.
“The Church proposes the example of numerous Saints who bore witness to and defended moral truth even to the point of enduring martyrdom, or who preferred death to a single mortal sin. In raising them to the honour of the altars, the Church has canonized their witness and declared the truth of their judgment, according to which the love of God entails the obligation to respect his commandments, even in the most dire of circumstances, and the refusal to betray those commandments, even for the sake of saving one’s own life.”
Even though it might seem, from a mere human point of view, that one ought to commit a sinful act, such as lying, in a particular dire circumstance, from a heavenly point of view, it is always an offense against God. There is no circumstance that justifies the knowing choice of an intrinsically evil act because God rights all wrongs, punishes all offenses, rewards all virtuous acts, and grants eternal life and happiness to those who persevere in what is good.
“The fundamental moral rules of social life thus entail specific demands to which both public authorities and citizens are required to pay heed. Even though intentions may sometimes be good, and circumstances frequently difficult, civil authorities and particular individuals never have authority to violate the fundamental and inalienable rights of the human person. In the end, only a morality which acknowledges certain norms as valid always and for everyone, with no exception, can guarantee the ethical foundation of social coexistence, both on the national and international levels.”
“These norms in fact represent the unshakable foundation and solid guarantee of a just and peaceful human coexistence, and hence of genuine democracy, which can come into being and develop only on the basis of the equality of all its members, who possess common rights and duties. When it is a matter of the moral norms prohibiting intrinsic evil, there are no privileges or exceptions for anyone. It makes no difference whether one is the master of the world or the “poorest of the poor” on the face of the earth. Before the demands of morality we are all absolutely equal.”
“But the negative moral precepts, those prohibiting certain concrete actions or kinds of behaviour as intrinsically evil, do not allow for any legitimate exception. They do not leave room, in any morally acceptable way, for the “creativity” of any contrary determination whatsoever. Once the moral species of an action prohibited by a universal rule is concretely recognized, the only morally good act is that of obeying the moral law and of refraining from the action which it forbids.”
The quotations above are from Veritatis Splendor
What makes an act intrinsically evil? The inherent ordering of an act toward an end, in terms of morality, called the moral object of the act, is what makes an act inherently licit or inherently illicit (immoral). Intrinsically evil acts are directed, by the very nature of the act, towards an evil moral object, an evil end.
It is not the attainment of that evil end that makes the act intrinsically evil, but rather its inherent ordering toward that end.
For example, the use of contraception is intrinsically evil because the act itself is inherently directed toward the deprivation of the procreative meaning from sexual acts. If a couple have sexual relations with contraception and they conceive (because contraception is not 100% effective), they have nevertheless sinned. For they deliberately chose an act that is inherently directed toward the deprivation of the procreative meaning of sexual acts.
If another couple has sexual relations without contraception, but they are unable to conceive due to old age, injury, or illness, they cannot achieve the procreative end toward which sexual relations is naturally and inherently directed. Yet they have not committed an intrinsically evil act, because the type of act that they chose is inherently ordered toward that good end of procreation.
What if a couple choose to use contraception outside of marriage? Is the act still intrinsically evil? Contraception is intrinsically evil because it deprives sexual acts of their procreative meaning. This deprivation occurs regardless of whether the sexual acts are marital or non-marital. Sexual acts are naturally directed toward procreation, even when the acts are non-marital.
What if the couple use contraception within marriage, but without a contraceptive intention? What if they intend to treat a medical disorder? Intrinsically evil acts, such as the use of contraception, are always immoral, regardless of intention or circumstances.
“Legitimate intentions on the part of the spouses do not justify recourse to morally unacceptable means (for example, direct sterilization or contraception).” (CCC, n. 2399).
Can the principle of double effect justify the use of contraception? No. The principle of double effect never justifies any intrinsically evil act. To be justified under that principle, the act must be good in itself, the act must not be intrinsically evil.
The rejection of the definitive magisterial teaching that certain types of acts are always immoral, regardless of intention or circumstances, is one of the most common heresies among Catholics today.
“It is therefore an error to judge the morality of human acts by considering only the intention that inspires them or the circumstances (environment, social pressure, duress or emergency, etc.) which supply their context. There are acts which, in and of themselves, independently of circumstances and intentions, are always gravely illicit by reason of their object; such as blasphemy and perjury, murder and adultery. One may not do evil so that good may result from it.” (CCC, n. 1756)