Is warning people about a man who is known to commit evil openly regarded as backbiting?

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Check below answers in case you are looking for other related questions:
If a person talks to himself about someone else who mistreated him, is that regarded as backbiting?
Backbiting About a Non-Muslim and Complaining to Seek Advice

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Complaining to Husband About Relatives
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Expiation for Gossip
If a person talks to himself about someone else who mistreated him, is that regarded as backbiting?
Backbiting About a Non-Muslim and Complaining to Seek Advice

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