Perhaps, this can and should be broadened a little. It is important that the Christian faithful know that they can approach priests outside of the confession with intimate or potentially harmful revelations and yet possess the general expectation of confidentiality (con+fidere = to trust with). Not all duties are merely legal. Many are moral.
Some general comments can be made about secrecy and confidentiality in Church ministry, although it would be necessary to evaluate any concrete and particular case in detail before giving particular opinion.
While a communication with a cleric, apart from sacramental confession to a priest (see c. 983), does not enjoy absolute or inviolate confidentiality, clerics do have a recognized heavier duty to preserve certain things which may be revealed to them in connection with the sacred ministry (i.e., the ordained ministry).
The general duty of all is presented in canon 220: No one is permitted to harm illegitimately the good reputation which a person possesses nor to injure the right of any person to protect his or her own privacy. This addresses both a right to reputation and to privacy which the Christian faithful possess and their obligation in regard to others. In one sense, willfully violating another’s reputation could result in severe ecclesiastical penalties (c. 1390). Indeed, reparation for damage would be required of someone unlawfully causing harm to another by a malicious or culpable act (c. 128). A person failing to take due precaution about something could be culpably negligent. The right to reputation and privacy (apart from sacramental seal) is not by itself absolute though, since the canon expressly considers the possibility of harming legitimately a reputation. For example, a diocesan bishop who makes known that a person has been excommunicated or removed from ministry would not inflict harm illegitimately, since these facts would need to be publicly known to protect the Christian faithful. So those personal rights have to be considered in light of the common good of the Church by church authority (c. 223). Individuals, for a just reason, can freely divulge secrets about themselves. But if they lawfully impose restrictions on the person to whom a confidence is given, it seems that one is obliged to keep the secret. The Catechism would be a useful source to consult on the broad moral issue here.
There are several forms of confidentiality in canon law, the inviolate seal of the confessional being the most obvious. Other cases when secrets must be kept involve religious life, penal and contentious tribunal trials. The bishop can determine the appropriate kind of secrecy in his curia (c. 471) and so can a superior in certain situations (c. 127). Persons can be bound to pontifical secrecy, there is also the notion of the secret of the Holy Office. There are also restrictions in regard to clergy and religious and candidates for orders or vows and communicating aspects of medical or psychological treatments or assessment.
Apart from that, a case can be made for ministerial secrecy on the basis of canon 1548 §2, 1º. This exempts a number of persons from the obligation to testify in a tribunal trial: clerics in regard to whatever was made known to them in connection with their sacred ministry; civil officials, doctors, midwives, advocates, notaries and others who are bound to professional secrecy, even by reason of advice rendered, as regards matters subject to this secrecy. This list is not an exhaustive one. For example, a case could be made that a lay parish staff member is obliged to maintain similar confidences. The code also treats the matter of confidential documents in a Church trial in a similar manner (c. 1546).
So my opinion is that a cleric need not draw upon any special status as a trained or certified professional in another discipline. The obligation can arise by virtue of a revelation made known in connection with the sacred ministry itself.
It seems to me that a duty of preserving ministerial confidence should be understood to exist if a) the person manifests an explicit and reasonable request to the priest, or b) revelation of the subject matter itself would illegitimately harm a person’s reputation in the common estimation, or c) the context of the discussion would indicate that confidentiality is implicitly requested. More could be said of this and said better, of course.
One difficulty that arises is determining when a conversation with a cleric is merely personal as opposed to one conducted in connection with the sacred ministry? But when a personal struggle is discussed with a priest, this seems to fall in the domain of a protected communication as far as Church law goes. A civil lawyer would have to be consulted in terms of possible civil protection though.
