Some writers claim that Émile Gaboriau was the author of the first detective novel. That is too simple, but he was certainly a pioneer in four respects. First, his novels fuse the short, tightly constructed, intellectually satisfying account of a mystery and its solution, practiced by Edgar Allan Poe, and the long, episodic, and sensational stories enjoyed by the French newspaper-reading public of the 1860’s. Second, Gaboriau was the first to introduce convincing false trails for the reader (and the police) to follow, and he provided ingenious variations of this device in later novels. Third, and perhaps most important, Gaboriau rehabilitated the official detective in fiction: Lecoq differs from his predecessors in being neither an incompetent against whose efforts those of a gifted amateur are contrasted nor a sinister agent of a repressive regime. Finally, Gaboriau gives authentic insights into judicial interrogations, police procedures, and scientific methods leading to the detection of crime. Despite the sensational episodes, gruesome scenes, and accounts of deductive reasoning and police activities, his novels reveal contemporary social conditions and attitudes and bear comparison with the work of the acknowledged masters of the realist and naturalist novels of the day.