Adverb
in propria persona
By the person themself; often used when a defendant is representing themself in court without an attorney.
When Humphries writes in propria persona his prose can scarcely contain its freight of cultivated allusions. He writes the most nutritiously rococo English in Australia today, but nobody will be able to inherit it. To know him would not be enough. You would have to know what he knows. Clive James