In ordinary usage a secret (secretum, from secernere, to set apart) means some hidden knowledge, something that is known only to one person, or to a very few. The question of secrets enters the moral sphere because a person has a right of ownership to his secrets. There is a moral obligation to respect this right. And the protection of the right is necessary in the interest of the individual and for the welfare of the community. Thus the obligation to respect the right of secrecy arises basically from the virtue of justice—from commutative justice primarily but also from social justice.
Since a person owns his secrets, others may not seek to acquire them unjustly, and if they do acquire them, justly or unjustly, they may not lawfully use them or further divulge them in any way contrary to the reasonable will of the owner. So long as secrets remain intact—that is, in the exclusive possession of their owner —they pose no general moral problems. Particular circumstances, however, could arise in which the owner of the secret would be bound to divulge the hidden knowledge if this divulgation were really necessary to prevent serious loss or injury to the public good or to innocent persons, and if it could be made without disproportionate loss to the owner.
The moral obligations and problems arise more immediately when the secrets have somehow passed from the owner and have come into the possession of another or of some few others. Traditionally moral theology begins its discussion of secrets at this point, and a secret is briefly defined as "the possession of some hidden knowledge belonging to another that may not be divulged."
Division. There are three kinds of secrets: natural, promised, and entrusted. This is a broad division and various subdivisions might be introduced under each class. But these subdivisions have no particular moral relevance except under the third class of entrusted secrets.
The Natural Secret. This secret is hidden knowledge concerning another that may not be divulged because its divulgence would cause pain, offense, or loss to the owner of the secret. The obligation to honor such a secret arises from the nature of things and thus derives immediately from the natural law. Violation of this obligation is a sin against justice and also against charity. It does not matter how the secret knowledge was acquired—whether by chance or by fraud. The sin committed by the violation is objectively grave if serious pain, offense, or injury results to the owner.
The Promised Secret. A secret of this kind is so called because its specific obligation arises from a promise made, after the acquiring of the hidden knowledge, not to divulge it. The content of the promised secret may have been freely revealed by the owner or may have become known by chance or even by fraud. The obligation that arises from a promised secret qua tale is one of fidelity to the promised word, which generally binds under pain of venial sin. Exceptionally, however, the person giving the promise might freely intend to bind himself in justice and sub gravi, and in these exceptional circumstances, violation of a promised secret would be a grave sin if the matter in issue were of grave consequence. It may happen also, indeed it will often happen, that a promised secret, by reason of its content, will also be a natural secret, and when this is so the principles governing violation of natural secrets apply.
The Entrusted Secret. A secret is of this kind when it is revealed by the owner to another on trust. That is to say, when the owner reveals it under a prior agreement or understanding—which may be express or implied— that the recipient will not divulge it to others. Thus an agreement to preserve the secret is a condition on which it is shared. The condition may be expressly stipulated— that is formally asked for and accepted; or it may be implicit—that is, implied in the relationship that exists between the parties concerned. The secret is shared on the accepted understanding that it will be conserved by the recipient because this person is in a position or office of trust vis-à-vis the owner of the secret. Consequently the implicitly entrusted secret is often identified with the official or professional secret. While this identification is not entirely complete, the professional secret is the most important, as well as the most usual, type of implicitly entrusted secret. This secret arises for instance, between a client and his legal adviser; between a patient and his doctor; between a priest and those who seek his advice confidentially extra tribunal, and at the highest level— indeed at a unique level—between the penitent and the confessor.
From the entrusted secret, by reason of the onerous contract or quasi contract involved in it, there arises an obligation of strict justice—a grave obligation exgenere suo. This obligation is additional to that which derives from the secret qua natural. Moreover, the preservation of professional secrets is necessary for the common good—to ensure free and confident access to the various levels of professional advice and, therefore, violation of these secrets is also an offense against social or legal justice. Professional secrecy is safeguarded in the provisions of Canon Law. Civil codes also generally grant privilege to at least some kinds of professional secrets.
Exceptions to Moral Inviolability. Leaving aside the question of the sacramental seal, which entails a unique inviolability, the obligation that flows from other secrets is not absolute. In general the obligation to observe the secret remains so long as the owner retains his right over it. He may voluntarily forgo this right— provided that doing so does not disproportionately injure others. It is often said that it may be presumed the owner of a secret forgoes his right to it whenever its observance would entail injury or loss to himself. This is certainly a reasonable presumption in regard to natural and promised secrets but it may not always be readily applied in the case of professional secrets because in these there is a nonpersonal factor to be considered, namely, the public good. A person may lose his right to have his secrets conserved. In estimating the cause that involves this loss of right and justifies revelation of a secret, account must be taken of the type of secret in question. The more serious its nature and its content, the more grave must be the cause required to justify its revelation. As a general guiding principle it can be said that the advantage gained from the revelation must always outweigh the loss sustained, with all relevant factors taken into account. This particular type of judgment always demands a delicate assessment of all the values involved.
The assessment is particularly difficult in the case of professional secrets, which, in addition to their contractual element, have a great social importance. Yet these secrets are not inviolable. The commonly accepted teaching of moralists is that it is lawful, even obligatory sometimes, to reveal a professional secret if its observance entails grave injury to the common good, to an innocent third party, to the professional person to whom the secret has been entrusted, or to the owner of the secret. But great caution must be exercised in applying these excusing causes. Professional secrecy must be jealously guarded as a feature of civilized living. In the exposition of the excusing causes it would be preferable, and indeed more accurate, to say that the professional secret must be sedulously observed unless its revelation is really necessary to prevent a disproportionately grave injury to the common good, to an innocent third party, to the recipient, or to the owner of the secret. The qualification "disproportionately" is very important, however difficult it may be to apply it, when some imponderable elements are in the issue. The professional secret is in possession, so to speak. It must, therefore, be evident after a careful balancing of all the factors that, as a result of the violation of the professional secret, the benefit accruing to the common good or to the individuals mentioned clearly outweighs the injury done to the personal and social values inherent in this type of secret. In fine, the revelation of a professional secret (apart of course, from the case of the free and justifiable permission of the owner) is lawful only as a last resort, that is, when the revelation is the only available means to prevent serious and imminent injury to the common good or to innocent individuals.
Bibliography: thomas aquinas, Summa Theologiae 2a2ae, 70.1. alphonsus liguori, Theologia moralis 3:970–972. b. h. merkelbach, Summa theologiae moralis, 3 v. (8th ed. Paris 1949) 2:852–856. t. a. iorio, Theologia moralis, 3 v. (4th ed. Naples 1953–54) 2:276–283. h. davis, Moral and Pastoral Theology, revised and enlarged by l. w. geddes (New York 1958) 2:422–425. r. e. regan, The Moral Principles Governing Professional Secrecy with an Inquiry into Some of the More Important Professional Secrets (Washington 1941) 20–25, 95–112. n. iung, Dictionnaire de théologie catholique, ed. a. vacant, 15 v. (Paris 1903–50; Tables générales 1951–) 14.2: 1756–64.
[j. l. mccarthy]