Gian Domenico graduated from La Sapienza University in Rome in Law. He was president of the Rome Criminal Chamber from 2006 to 2010 and acted as Enzo Tortora’s lawyer.

For years, he was the defender of Marco Pannella, Emma Bonino, and other radical militants in the criminal trials born from the acts of civil disobedience. He has participated and acted as a defense lawyer in many important national trials. From October 2018, he has been the President of the Union of Italian Criminal Chambers.