In the Roman Catholic Church, a plenary council is any of various kinds of ecclesiastical synods, used when those summoned represent the whole number of bishops of some given territory.
Later usage has restricted the term plenary to those councils which are presided over by a delegate of the Apostolic See, who has received special power for that purpose, and which are attended by all the metropolitans and bishops of some commonwealth, empire, or kingdom, or by their duly accredited representatives.
The Episcopal Conference itself, a permanent body of bishops from a territory, is a relatively modern structure, with the earliest formed in Switzerland in 1863 and only confirmed as policy at Vatican II.
In contrast, the need to meet for critical matters means that Plenary Councils, called only when necessary to justify the time and effort required, are quite ancient.
The patriarchs of Constantinople convoked, on special occasions, a synodos endemousa, at which were present bishops from various provinces of the Greek world who happened to be sojourning in the imperial city, or were summoned to give council to the emperor or the patriarch concerning matters that required special episcopal consultation.
The bishops in these synods were not gathered together because they belonged to certain ecclesiastical provinces, but because they were under the same civil government, and consequently had common interests which concerned the kingdom in which they lived or the people over whom they ruled.
As ecclesiastical jurisdiction is necessary for the person who presides over a plenary or national synod, this name has been refused to the assemblies of the bishops of France, which met without papal authorization in the seventeenth and eighteenth centuries.
After the establishment of the empire, Napoleon I held a great convention of bishops at Paris (1811), and is said to have been much incensed because Pius VII did not designate it a national council.
Such episcopal conventions have been praised by the Holy See, because they showed unity among the bishops, and zeal for asserting the rights of the Church and the progress of the Catholic cause in their midst, in accordance with the sacred canons,[8] but, as the requisite legal forms and proper hierarchical authority are wanting, these congresses of bishops do not constitute a plenary council, no matter how full the representation of episcopal dignitaries may be.
Summons to a national or plenary council is to be sent to all archbishops and bishops of the nation, and they are obliged to appear, unless prevented by a canonical hindrance; to all administrators of dioceses sede plena or vacua, and to vicars capitular sede vacante; to vicars Apostolic possessed of episcopal jurisdiction; to the representatives of cathedral chapters, to abbots having quasi-episcopal jurisdiction.
In the United States, custom has sanctioned the summoning of auxiliary, coadjutor, and visiting bishops; provincials of religious orders; all mitred abbots; rectors of major seminaries, as well as priests to serve as theologians and canonists.
In former times, such councils often condemned incipient heresies and opinions contrary to sound morals, but their decisions became dogmatic only after solemn confirmation by the Apostolic See.
If, consequently, anything be found in their acts contrary to the common law of the Church, it would have no binding force unless a special apostolic derogation were made in its favour.
Archbishop Phillip Wilson of Adelaide gave evidence[39] before the Royal Commission into Institutional Responses to Child Sexual Abuse that the plenary council was the appropriate church forum to respond to the child sexual abuse issue, rather than national or diocesan synods because: In the system, the really important gathering for the local Church is called the plenary council.
The plenary council has the ability to make regulations and rules, so it has a legislative power, which makes it a very important part of the way in which the life of the Church operates.However, because this issue is significant in many other territories, there is potential for the further revival of this long neglected form of governance through plenary councils in other jurisdictions if it is seen as being effective.