Eugène François Vidocq (1775 – 1857) was a French criminalist, often regarded as the father of criminology. Leading a tumultuous life, Vidocq was initially a criminal, but later became the director of the French judiciary police and eventually the head of the first known private detective agency.
Vidocq was born in 1775, spending his youth as a petty thief. He was frequently imprisoned, and by the French Revolution, he used the punishment as a means to avoid starvation. As the Assassin Arno Dorian found Vidocq imprisoned, he offered police chief Charles Cochon de Lapparent to assist in fighting crime. Although Lapparent declined, Vidocq revealed that the police chief had been unable to solve numerous murders. Vidocq pointed out that Arno could solve the murders, and Lapparent would receive the credit. The police chief then agreed to accept Arno's help.
While Lapparent tried to sleep, Vidocq called Arno to his cell. He claimed that he could help the Assassin solve the murders, possessing knowledge of the goings on in the streets of Paris. Arno questioned what interest Vidocq had in solving murders, to which he responded that Lapparent was unwilling to do anything about the crime in the city, removing any hope of making Paris a better place to live. He claimed that he also wanted to help in order to pass the time. Vidocq gave Arno instructions on how to solve murders properly, and would point him to murder cases across Paris throughout the revolution.
By the Napoleonic era of the early 19th century, Vidocq was working as an informant for the police, eventually joining their ranks. In his new position, his former association with thieves proved advantageous. He became one of the forefathers of the deductive crime-solving method, and founded the unit that became the Sûreté, the foremost crime-fighting organization in France. Working on both sides of the law, Vidocq's friends in the world of crime became invaluable in his work as a detective.