A detective is an investigator, usually a member of a law enforcement agency. They often collect information to solve crimes by talking to witnesses and informants, collecting physical evidence, or searching records in databases. This leads them to arrest criminals and enable them to be convicted in court. A detective may work for the police or privately.
Police detectives investigating a homicide in Oklahoma City, Oklahoma, United States
H Division, of police detectives, including Frederick Abberline (left, with cane), at Leman Street police station, of the London Metropolitan Police, two years before the Jack the Ripper serial killer murders of 1888. Photograph circa 1886
Allan Pinkerton (pictured here circa 1861) was, in 1850, a detective of the Chicago Police Department and, in 1851, the founder of the Pinkerton Detective Agency.
Edward Bonney, an American bounty hunter and amateur detective from Iowa who in 1845 infiltrated the "Banditti of the Prairie", wrote the 1850 book The Banditti of the Prairies: or, The murderer's doom, a tale of Mississippi Valley and the Far West; woodcut from 1850.
A private investigator, a private detective, or inquiry agent is a person who can be hired by individuals or groups to undertake investigatory law services. Private investigators often work for attorneys in civil and criminal cases.
Private detectives can perform surveillance work on behalf of individuals
Sherlock Holmes, the world's most famous fictional private investigator
1859 illustration of Vidocq arresting a robber after tracking him down
