I read in a comments box on an article ("The Mind of Francis: Denying Communion") by Thomas Reese at the National Catholic Reporter, "To deny communion to someone presumes to know what only God can know...the heart of the recipient." This is not completely true. There are in Canon Law external forum conditions for being admitted to Communion. For instance, whether you are baptized or not. Whether you publicly give scandal (without public repentance) is also external forum.