Spouses should not attempt joint sacramental confession
I believe, however, that there are formidable canonical and practical objections to joint sacramental confession, and I set them out for consideration.
Deitzen's basic argument runs thus: there is no express canonical or liturgical prohibition against spouses confessing sacramentally in each other's presence, so "couple's confession" is licit. But even if, pro arguendo, no norm expressly prohibits joint confession, one may still ask, So what? There is no canon against the faithful attending Mass drunk or naked, but surely we cannot read the law's "silence" as approval, qualified or otherwise, for such practices. The Church could not possibly identify in advance and prohibit every illicit practice that the faithful might think of. Inclined though I am to give wide play in canon law to the legal maxim Libertas praesumitur (Freedom is presumed), joint confession is an instance where that worthy principle must yield to weightier considerations.
Indeed, I suggest that it is clearly discernible from several canonical norms that joint confession should be avoided. Ironically, Deitzen identifies these norms but seems to miss their obvious (to me, anyway) implications.
1. Deitzen acknowledges that Canon 960 holds that "Individual and integral confession and absolution constitute the only ordinary means" of celebrating the sacrament of confession, but he fails to include the next clause of the canon: "only physical or moral impossibility excuses from confession of this type." The phrase Deitzen omits seems fatal for his argument: Standing alone, I think it defeats the liceity of "couple's confession" on Deitzen's facts: one cannot plausibly suggest, let alone prove, that it is morally impossible for one spouse to confess his or her sins except in the presence of the other spouse.
2. Deitzen also appeals to Canon 990 (authorizing an interpreter to assist one confessing sins) to show that one's confession can be made in the presence of another. But again, so what? The very existence of a canon permitting a penitent to use a translator reinforces the prior canonical expectation that sacramental confession is to be celebrated privately, a third party being authorized only to make someone's confession possible in the first place! If I may be pardoned a drift toward the ridiculous, interpreted confessions are not analogous to joint confessions for another reason: having interpreted the confession of a penitent into the language of the priest, the interpreter does not then confess his or her own sins in the presence of the penitent!
3. Deitzen misconstrues Canons 961 and 962 (on the absolution of multiple penitents in urgent cases) in wrongly stating that general absolution authorizes "general confession and absolution" for multiple penitents (my emphasis). These canons do no such thing; plainly, they provide for general absolution without confession of sins; individual confession is performed later.
There are additional problems with Dietzen's description of the "seal" that might arise from joint confession, and frankly I see no way to limit this practice, once admitted, only to married couples, but by way of conclusion, I would add a practical point: the modern practice of individual confession is designed to foster freedom and candor. Joint confession would undermine these values.
It takes no imagination to see that "couple's confession", while it might at first seem like an intimate, bonding experience, can quickly become an occasion to avoid revealing important details about the species and numbers of one's grave sins (Canon 988); this in turn can deteriorate into an excuse to avoid confessing at all, or it can spark spousal suspicions as to why going to confession together was okay last time, but not this time. Worst of all, "couple's confession" can result in the coercion of an unwilling spouse, which coercion might not be apparent to the confessor at the time. But guess who will later be blamed for having celebrated the joint confession?
In sum, I see no legal or pastoral support for the practice of joint confession, spousal or otherwise. The faithful should be dissuaded from attempting to celebrate the sacrament under these circumstances, and I would strongly discourage priests from becoming enmeshed in such an improvident practice.
Some additional thoughts: (1) My analysis does not address the validity of joint confessions/absolutions but, as is well known, sacraments are hard to break; they might well be celebrated illicitly, but still validly. (2) Joint confession introduces the novel prospect of one penitent being sufficiently disposed for absolution (Canon 980) but the other not. (3) While in common parlance the concepts of "privately" and "individually" are distinguishable, in the pastoral practice of confession, they have been viewed as interchangeable. This is, of course, Deitzen's point, that perhaps they should not be so viewed and that confession need not be "private" to be "individual". But aside from the fact that Canons 990, 961, and 962, among others, seem to assume that "individual" confession is "private", and in light of my practical concerns above, I think Deitzen has the burden of demonstrating why two terms that have been assumed as interchangeable for centuries should sudddenly no longer be understood that way before passing on pastoral changes that could have grave repercusssions for individuals seeking this sacrament. Something stronger than "There's no rule expressly prohibiting it" seems in order. (4) If one admits any third party, not a translator (and, okay, not a small child who cannot be left unattended for the time it takes to make confession) to be present at confession, why limit that concession to third parties (of any sort) making confessions? Why not permit attendance by other non-confessing parties who in turn might have any number of motives (known to the priest or not) for wanting to be present? This scenario offers its own host of serious pastoral (and for that matter, civil law immunity) questions.
Update: November 3, 2007. Fr. Deitzen, after communication with the Congregation for Divine Worship and Sacraments, has basically withdrawn his assertion that couples may receive the sacrament of confession together.