High Quality Content by WIKIPEDIA articles! Thomas "Tom" Feargal Hagen is a fictional character in the Godfather books and films. He was portrayed by Robert Duvall in the films. He is the informally adopted son of Don Vito Corleone and serves as the family lawyer and consigliere (legal advisor). Mild-mannered and soft-spoken, he often serves as a voice of reason within the family. The novel and first film establish that he is of German-Irish ancestry.