The decision of Benedict XVI to follow the precedent of Celestine V, who was pope for less than 18 months (13 Dec 1292–19 May 1294), raises the fascinating possibility that the papacy could revisit other ancient traditions that have since fallen into neglect.
One of these is the major constitutional reform introduced into the Church in 1059 by another pope, Nicholas II, who established the principle that to be canonically elected, a pope needed to be chosen with the assent not just of the cardinal bishops and other cardinal clergy, but of the whole of the Church: 'and then the rest of the clergy and the people shall approach to give their assent to the new election' (Gratian, Decretum 1.23.1).
As no mechanism was implemented to enforce this part of the constitutional reform, the papacy has failed for centuries to live up to its own canon law. Any new pope constitutionally needs the assent of the entire Church.
Nicholas II was challenging a system that had then prevailed for several centuries, whereby the Pope was effectively appointed by the Holy Roman Emperor. His establishment of a College of Cardinals was explicitly intended to challenge a system of ecclesiastical appointment that had become notoriously corrupt.
The notion of a cardinal (literally a hinge) has nothing to do with the hierarchy of holy orders. There were originally cardinal deacons and priests as well as cardinal bishops, each representing their particular grade within the Church. The text of the 1059 constitutional reform, which became part of canon law, makes clear that the papal election needed the support not just of the cardinals but of the clergy and people as a whole.
If the Church is serious about the need for reform of its governance it would do well to revisit the major constitutional reforms established in the 11th century. There is no reason why the category of cardinal could not be restored to those in the Church below the rank of bishop, or indeed be given to lay men and lay women.
The College of Cardinals is meant to be a representative assembly. In the 11th century, literacy outside the clerical and monastic orders was not widespread. The appointment of cardinals was intended to be a circuit breaker, to identify talented individuals outside the aristocratic elite that traditionally governed the Roman Church. A new pope needs to consider ways of returning to the reforms initiated by Pope Nicholas II.
Needless