What other possible explanation could there be for Sylder's driving fast to elude the police?

McCarthy never makes this background explicit, instead preferring to insert it indirectly into the action of the story itself. There is this same indirectness in Sylder's escape from the police. Given that the last scene with Sylder involved him dumping Kenneth Rattner's body into a pit, one might assume that he was running away for fear of being arrested for murder.