In Empathy, when you go to history, you have the option to delete all history and not for only a specific user.
How to delete the history of a specific user in Empathy people nearby account with preserving the history of other users?
The logs from Empathy (using the telepathy library, hence the naming) are under
(Note that this is a hidden directory - use the terminal or
Logs are stored in this directory in the structure
Delete as appropriate.
The logs (since Empathy 2.31.4) are saved in