Above the door to the sacristy is a monument to Pope Leo XIII, who is buried in the church. The monument is by Giulio Tadolini 1907. The work is considered his masterpiece. The main statue shows the pope standing on his green basalt sarcophagus, in a posture as if he were acknowledging the cheers of a crowd. The detailing of the embroidery and lace on his vestments are very well carved. Two allegorical statues flank the doorway, The Church in Mourning on the right and The Working Man on the left.