What is the theme in The High Window by Raymond Chandler?

Justice is the main theme of the book. Marlowe is not especially concerned with seeing that traditional justice is served. He sometimes alters evidence and refuses to give confidential information to the police that might aid their murder investigation. When he accidentally discovers two bodies he covers his involvement by wiping his fingerprints and other evidence from the scene. When he finds Vannier's body, he alters the crime scene to make it look like a suicide.