If you look at the canons on ordination, the requirements for validity are minimal. Part of the reason is to prevent the situation of invalidly ordained clerics performing invalid acts of ministry to the detriment of souls. Consequently the canonical threshold is low.
The requirements for validity are threefold. Everything else required for ordination by the law is for lawfulness rather than validity itself.
- Canon 1012: The minister of sacred ordination is a consecrated bishop.
- Canon 1024:Only a baptized male validly receives sacred ordination.
- In light of canon 2 which “canonizes” liturgical laws unless contrary to the code, the proper form of the Rite of Ordination would be required for validity as well. (Also see c. 1009 §2, orders are conferred by the imposition of hands and the consecratory prayer which the liturgical books prescribe.)
Canon 1041 and 1044 treat irregularities regarding receiving orders and exercising orders already received, respectively. An irregularity impedes the lawful reception of orders or the lawful exercise of orders already received. However, an irregularity does not render ordination invalid.
An irregularity at the time of ordination or subsequently by itself would not render sacramental actions of a priest, such as confecting the Eucharist, invalid. It would “only” render them illegal, or contrary to law.
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(For the valid administration of penance, the valid witnessing of matrimony, and even the valid conferral of confirmation, certain faculties * are needed, but that is a separate matter.)*
Canon 1041, 1º would illustrate this for candidates for ordination: [The following are irregular as regards the reception of orders:]
“1º one who labors under some form of insanity or other psychic defect due to which, after consultation with experts, he is judged incapable of rightly carrying out the ministry.”
Canon 1044 revisits this about the already ordained:
“§1. The following are irregular as regards the exercise of orders already received: 1º a person who has illegitimately received orders while he had an irregularity precluding his receiving orders. . . . §2. The following are impeded from exercising orders: 1º a person who has illegitimately received orders while he was bound by an impediment precluding his receiving orders; 2º a person who is afflicted with insanity or some other psychic defect mentioned in can. 1041, 1º, until the time when the ordinary after consultation with an expert, permits him the exercise of that order.”
The discussion has been that true same sex attraction presents such a psychic defect to that one would be judged incapable as the canon describes to receive orders. What the document may do is to tie true homosexual orientation to the determination of such a psychic defect rather than requiring the consultation mentioned in those canons.
As to clerics already ordained, that topic would seem to be outside the scope of a document on seminary formation.
“Some church officials have questioned whether some ordinations might even be considered invalid because of homosexuality.”
Therefore, it is totally unclear that there is a basis in the law, as it exists and is treated above, that would lead to this conclusion. Unless we know the names of the officials and their reasoning, not much more could be said.
The only thing I could conjure up is the belief that there was a defect of intentionality on the part of a bishop to ordain or the man to be ordained. But that would need a canonical trial.
As noted, the Church is loathe to declare ordinations invalid because of the repercussions.*
