More interesting quotes from this link
Thus, Canon 813.2 of the 1917 Code of Canon Law declared: “The minister serving at Mass may not be a woman, unless, there being no male available, for a just reason and with the proviso that the woman answer from a distance and in no case come up to the altar (ad altare accedat).”
This paragraph was not included in the 1983 revised Code of Canon Law. However, the need of an altar server was also dropped in the revised Code.
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Paragraph 1 of the Instructions given by the Congregation for Divine Worship and the Sacraments points out that permission given by some bishops for the use of female altar servers “can in no way be considered as binding on other bishops.” The Congregation bases this point upon the original wording of Canon 230.2, namely, that “all lay persons may carry out the functions of commentator, singer, or other functions.” However, there is here special meaning regarding female altar servers.
The implication is that the general liturgical norm prohibiting female altar servers remains in existence, so that in general women may not serve at the altar unless a local ordinary intervenes by a positive act and grants permission for his territorial jurisdiction. Thus, the Congregation has clarified the authentic interpretation to mean that
an indult is given to diocesan bishops to permit the use of female altar servers
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In fact, according to paragraph 3 of the Instructions, “If in some diocese, on the basis of Canon 230.2, the bishop permits that, for particular reasons, women may also serve at the altar,
this decision must be clearly explained to the faithful in the light of the above-mentioned norm.” The indult is not, therefore, intended as a general extension of the law of Canon 230.2 or as a permission that went into effect everywhere in the Latin Church, but only “in some diocese” or other “for particular reasons.”
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d) It will always be very appropriate to follow the noble tradition of having boys serve at the altar, and thus the obligation to support such groups of altar boys will always continue
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From the juridical data gathered above,
it seems clear that the general law prohibiting female altar servers remains in effect as a general law, notwithstanding the entry into effect of the authentic interpretation of Canon 230.2, except where it is suspended by the positive intervention of a diocesan bishop for his own territory.
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With the new permission [of allowing female altar server], the male presbyterium disappears entirely by derogation from a law which, nevertheless, remains in effect for the universal Church.
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Certain conclusions would seem to follow from this analysis.
The first is that the use of altar girls does not necessarily imply a step forward in the liturgical practice of the Western Church. The Holy See “respects the decision” of certain bishops in the sense that it no longer regards such a decision to be an abuse of the law, but
this does not mean that the Holy See recommends and advocates the use of women altar servers as an improvement in the liturgical practice of the Church. It is more a yielding to pressure, together with, perhaps, a certain diffidence in its own ability to judge, than it is a positive teaching. Nor do these Instructions take up the theological, mystical, psychological, and social realities underlying the noble tradition of male servers only, which the Congregation for Divine Worship and the Sacraments certainly would have had to do before proceeding to overturn the constant discipline and practice of the past two thousand years.
No more female altar server please.