Jus novum (c. 1140-1563) Jus novissimum (c. 1563-1918) Jus codicis (1918-present) Other Sacraments Sacramentals Sacred places Sacred times Supra-diocesan/eparchal structures Particular churches Juridic persons Philosophy, theology, and fundamental theory of Catholic canon law Clerics Office Juridic and physical persons Associations of the faithful Pars dynamica (trial procedure) Canonization Election of the Roman Pontiff Academic degrees Journals and Professional Societies Faculties of canon law Canonists Institute of consecrated life Society of apostolic life Romano Pontifici eligendo was the apostolic constitution governing the election of popes that was promulgated by Pope Paul VI on 1 October 1975.
It set the maximum number of electors at 120 and restated in a more formal context the rule he had already instituted that cardinals over the age of 80 not participate in electing a pope.
Pope Paul also imposed strict regulations on the physical organization of a conclave, including a requirement that the windows of the Sistine Chapel be boarded up.
Cardinals found the restrictions excessive during the two conclaves of 1978 and Pope John Paul II dropped them in his 1996 apostolic constitution Universi Dominici gregis (1996).
Pope Paul had been crowned in June 1963 following his election but abandoned the wearing of a papal tiara in November 1964.