Why does Inspector Javert keep chasing Jean Valjean?

Throughout the course of Les Miserables, the protagonist, Jean Valjean, finds himself pursued by Police Inspector Javert. Javert is determined to bring the ex-convict to justice--that is, throw him back into the galleys. In the end, however, Valjean is given an opportunity to kill Javert, and refuses, his merciful character unwilling to murder a man.

Javert is overwhelmed and stunned by this display of kindness from a man he considered a criminal. Instead of living any longer with the confusion he feels over Valjean's grace and mercy, Javert takes his own life by jumping off a bridge.