how is De Villefort devoteful to his career before chapter 10?

Monsieur de Villefort is the public prosecutor of Marseilles who was responsible for Dantes' incarceration. Much to Villefort's chagrin, Villefort's father was a known Bonapartist, thus his policy for Bonapartist conspirators was harsh. He sought to protect his own name. He succeeds in becoming the public prosecutor in Paris.