The fact that a person is incapable of performing juridical acts for himself does not make him incapable of acting as a mandatary.
Civil Code
2015 English source edition · Current applicability not established.
This is the 2015 English-language edition attributed in its front matter to the Ministry of Justice. Eri Atlas has not independently verified the translation, later changes, or whether the text is currently in force. Nine passages are incomplete in the available scan and are identified where they occur.
Article 2377
Incapacity · Preserved transcription; page attribution imported from the source collection. Verify against the original.
A juridical act performed by a mandatary pursuant to a mandate granted by an incapable is valid, void or avoidable just as it would have been, had it been performed by the incapable person himself.