Question: Is it permitted to praise your friend in front of other people?
Short Answer: It is forbidden (avak lashon ha’ra) to speak positively about your friend in front of his enemies or, even in front of friends if you excessively speak positively about him.
Question: Is it permitted to share with others lashon ha’ra that is public information, such as a decision from a beis din?
Short Answer: Negative information about someone, even if public, such as a ruling of a beis din, should not be shared with others on a consistent or organized basis, especially if the intent is to spread gossip.