Detraction is a sin against the Eighth Commandment which consists in revealing another's faults and failings to persons who did not know them, without an objectively valid reason (CCC 2477). Even if the information is true, the act is sinful (CCC 2477).
Justice and Reputation
Everyone has a right to their reputation. Respect for the reputation of persons forbids every attitude and word likely to cause them unjust injury (CCC 2477, 2479). Detraction requires reparation (CCC 2487).
Frequently Asked Questions
Is it ever okay to reveal someone's faults? Yes, if there is a grave and objective reason, such as preventing harm to the common good (CCC 2477).
May the Lord bless you and keep you.