Six years ago Rorate posted on who is allowed to sing the Passion during Holy Week. The answer, we thought, was pretty clear, but apparently not everyone agreed. Some traditional Latin Masses employed laymen to chant entire parts of the Passion, as performed via the novus ordo.
To that end, the Pontifical Commission "Ecclesia Dei" was consulted on this issue. Here is the response:
To summarize, the privilege to chant the Passion begins at the diaconate level for all three parts of the Passion (except for the turba portion of the synagoga).
PCED's response is consistent with its declarations over the years on who may fulfill the role of subdeacon at a Solemn High Mass. This consistency respects the nature of major orders and the clerical state, sounding a theme that it is not licit for a random layman to fill in for clergy -- even if the substitution is going to result in a visibly and/or audibly more beautiful liturgy. Liturgical law must prevail over even a well-intentioned effort to improve quality.
We hope this puts to rest any practice to the contrary.
