at the Death or Resignation of the Supreme Pontiff
When the
Pope
resigns or dies, before the election of a successor, the
Petrine See of Rome
becomes vacant (sede vacante).
The canon laws governing this period of interregnum are specified in the Apostolic Constitution
Universi Dominici gregis, later modified by the Motu ProprioNormas nonnullas.
During the period of sede vacante, certain offices in the
Roman Curia
are suspended, and some offices have special roles as specified in Universi Dominici gregis.