Few legal institutions exist that are as timely as the conclave and that at the same time capture the interest of public opinion in such a generalized way. test of this are the more than 5000 journalists accredited to the Vatican to cover the assembly of the high school cardinals from which Benedict XVI's successor will be elected.

The conclave is a peculiar elective mechanism, which pursues different objectives. On the one hand, it ensures that the election of the Roman Pontiff is carried out with a certain celerity, in order to avoid the logical damage of a vacant see for too long. To this end, the meeting of the electors is organized in the same place and under a somewhat ascetic regime.

No less important is to guarantee the secrecy of the electoral process to the outside world. This circumstance protects, to a certain extent, the freedom of the voters, who can thus vote in conscience, free from the interference of political or media agents.

The functioning of the conclave, as we know it today, is the result of a long process. It is not surprising that the instrument in charge of regulating access to the top hierarchical position in the Catholic Church has been subject to continuous revisions and improvements over the centuries. The following is a brief synthesis of the main milestones in the evolution of this institution.

During the first Christian millennium the pope was elected by means of the diffuse and traditional procedure of the election made by the clergy and the people of Rome. This system suffered the interferences of the imperial power (both of the West and of Byzantium) and of the Roman aristocracy with different intensities according to the epochs.

The figure of the conclave begins for the first time to be glimpsed when in 1059 Nicholas II reservation the pontifical election to the cardinals. Although the measure does not triumph immediately, it sets the fundamental instructions of the later development of the machinery of election of the pontiff. With the beginning of the second millennium, few will be the popes who will not legislate on this point.

In 1179 Alexander III established the necessity of two thirds of the suffrages for the election of the pope. This qualified majority could lead to very lengthy elections (sometimes after more than a year of negotiations), hence the "sequestering" of the electors under lock and key (hence the term conclave) to force the election of the new pope was taken to internship . This system was first put on internship in 1216; in 1241 the senator of Rome locked the cardinal electors in the prison ruins of Nero's complex; and in 1268 Alberto de Montebono imprisoned the cardinals in the papal palace of Viterbo.

In 1275 Gregory X fixed the place of confinement where the pope died, indicating that the cardinals should wait for a maximum of 10 days, regulating the food per diem expenses of the electors and prohibiting the enquiry to the exterior. In 1562 Pius IV concretized the limitation of the electoral systems admitted to four forms: the inspiration (act of extraordinary acclamation), the commitment (to delegate to a limited issue of cardinals), the scrutiny and the access (which allows any cardinal who wishes, at the end of a scrutiny, "access" to another candidate).

The Bull Aeterni Patris (15.XI.1621) of Pope Gregory XV takes up norms already substantially received from the past, but systematized and developed in a more perfect way: it details the ways to enter the conclave, elaborates a ceremonial, forbids cardinals to vote for themselves and tries to circumscribe and limit the cases that could give rise to a null election.

The Catholic nations are no strangers to the system of election: for reasons of politics, both international and ecclesiastical, they interfere in the conclave with the interposition of vetoes directed at one or the other candidate. The civil service examination of a veto (technically known as exclusive) against a candidate by Catholic sovereigns could not be ignored without exposing the elected to disrepute or political marginality. Since the 16th century, exclusivity has been gaining ground, especially on the part of the Spanish crown. And throughout the 18th century the conclave reflected political balances in a phase of transformation.

During the time of the revolutions, the popes tried to prevent various emergency situations: Pius VI established that in an extreme case of a vacant see status , the absolute majority of the cardinals would be empowered to resolve any eventual indecision or dilemma about the way to celebrate the conclave. For Pius IX the council is ipso facto dissolved by the death of the pontiff and determines that if the pope dies outside Rome the conclave will take place where the majority of the high school cardinals can be gathered. For his part, Leo XIII established that in case of kidnapping of the pontiff, the latter would be considered dead due to inaccessibility.

The system of election of the Roman Pontiff was consolidated in the 20th century, especially with the Apostolic Constitution Vacante Sede Apostolica ( 1904) of Pius X, which codified all previous law in this regard. In 1946, Pius XII added that the Secretary of State and the heads of congregations should resign from the vacant See and imposed, among other measures, new oaths of secrecy ( reference letter to the means of telegraphic, telephonic, photographic and cinematographic communication). In fact, John XXIII put an end to the ceiling of 70 cardinals set in 1586 by Sixtus V. Paul VI confirms that only cardinals under 80 years of age have the right to elect the Roman Pontiff and establishes a maximum of 120 cardinal electors.

The current regulation of the election of the Roman Pontiff is contained in the Apostolic Constitution Universi Dominici Gregis, promulgated by John Paul II in 1996 and with slight modifications made by Benedict XVI in 2007 and a few days before his Withdrawal to the pontificate.

The succinct notes on the evolution of the conclave show, on the one hand, the fascination for an institution in which so many spiritual and human interests converge. The interference of the political powers has been constant throughout history, and if today they seem to have been largely overcome, it is no less true that the figure of the pope continues to be a moral reference with great impact on today's civil society. On the other hand, it can also be seen how the conclave has progressively taken shape in order to guarantee a clear process, without fissures, in the election of the person who occupies the apex of the ecclesiastical hierarchy. In this way the law (in this case the canon law) goes as far as it can: it offers the necessary instructions so that the election takes place in a context of spiritual recollection and free, as far as possible, from external interference. In turn, this framework of juridical security is Pass so that the spiritual elements that are proper to the designation of the head of the Catholic Church, a divine institution but inserted in the midst of temporal realities, may be given their full force. Under the guide of the Holy Spirit and protected by the enclosure "under lock and key", the cardinal electors now have the floor.