Yesterday was the feast day of St. Callistus, the only redeemed criminal to become Pope, and one of the patron saints of this apostolate.
Excerpt from American Catholic.
"The most reliable information about this saint comes from his enemy St. Hippolytus, an early antipope, later a martyr for the Church. A negative principle is used: If some worse things had happened, Hippolytus would surely have mentioned them.
"Callistus was a slave in the imperial Roman household. Put in charge of the bank by his master, he lost the money deposited, fled and was caught. After serving time for a while, he was released to make some attempt to recover the money. Apparently he carried his zeal too far, being arrested for brawling in a Jewish synagogue. This time he was condemned to work in the mines of Sardinia. He was released through the influence of the emperor's mistress and lived at Anzio (site of a famous World War II beachhead)."
Read more about him, plus a picture, here.