The pope can call for a consistory when he deems it necessary to meet with the College of Cardinals. And these meetings can take two forms: ordinary and extraordinary consistories. Canon Law clarifies that ordinary consistories are normally attended by cardinals residing in Rome, while extraordinary consistories convene all cardinals to discuss serious matters.
In some cases, consistories may be public, allowing some non-cardinals to enter. This often happens during a consistory that decides canonization dates or one that creates new cardinals. The latter traditionally involves the participation of the families of the new cardinals or diplomatic representatives of their countries.
Pope Francis has convened at least three extraordinary consistories. One in 2014 to speak about family issues, another in 2015 to address reform of the Roman Curia and another in 2022 to discuss the reform that had been put in place. Pope John Paul II also held several extraordinary consistories, for example, to analyze the financial situation of the Holy See.
Sometimes consistories even include big surprises. In 2013, Pope Benedict XVI announced his resignation at an ordinary public consistory that was scheduled to discuss the canonization of several Blesseds of the Catholic Church.
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