Martyrs, or people who were killed for their faith, get a free pass and can be beatified without a miracle. A miracle is needed, however, for martyrs to be canonized.
JOHN XXIII AND JOHN PAUL II
John Paul's record sprint to sainthood started during his 2005 funeral Mass, when chants of "Santo Subito" or "Sainthood Now" erupted from the crowd. Bowing to the calls, Pope Benedict XVI waived the typical five-year waiting period before a saintly investigation can begin and allowed the process to start just weeks after his death.
The rest of the process followed the rules: John Paul was beatified in 2011 after the Vatican certified that a French nun suffering from Parkinson's disease was miraculously healed after she prayed to him. A Costa Rican woman whose inoperable brain aneurism purportedly disappeared after she prayed to John Paul was the second miracle needed for canonization.
"I was scared. I just wanted to die at home," Floribeth Mora told reporters Thursday of her state of mind after receiving her aneurism diagnosis. She said she saw a photo of John Paul in a magazine on the day he was beatified. "And from that moment I started a new life."
John XXIII was beatified in 2000 after the Vatican certified that the healing of an Italian nun suffering from a gastric hemorrhage was miraculous.
Pope Francis, very much a spiritual son of John, waived the Vatican rule requiring a second miracle so that John could be canonized alongside John Paul.
While popes past have tended to follow the saint-making process precisely except for occasional exceptions, Francis has waived the rules now on several occasions. On Thursday, for example, he presided over a Mass of thanksgiving for a Brazilian saint he declared without the necessary miracle.