

Guerry's first work on what would come to be called moral statistics was a large, one page sheet containing three shaded maps of France, prepared together with the Venetian geographer, Adriano Balbi in 1829. Guerry was so fascinated with these data, and the possibility to discover empirical regularities and laws that might govern them, that he gave up the active practice of law to devote the rest of his life to study crime and its relation to other moral variables. Guerry worked with the data on crime statistics in France collected as part of the General office for administration of criminal justice in France, the first centralized national system of crime reporting. Shortly after, he was employed by the Ministry of Justice. About 1817-1820 he studied at the Imperial College of Tours (now the Lyceum Descartes, founded in 1807) and subsequently studied law at the University of Poitiers.Ībout 1824–1825 he moved to Paris and was admitted to the bar as a royal advocate.

Guerry was born in Tours, Indre-et-Loire, the only child of Michel Guerry, a building contractor, whose family had a long history as innkeepers, merchants, farmers and trades-people.
