A private investigator often abbreviated to PI and informally called a private eye , a private detective , an inquiry agent or informally a private dick 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.
Much of what private investigators did in the early days was to act as the police in matters for which their clients felt the police were not equipped or willing to do. Official law enforcement tried many times to shut it down. In , police arrested him in suspicion of unlawful imprisonment and taking money on false pretences after he had solved an embezzlement case. Vidocq later suspected that it had been a set-up.
He was sentenced to five years and fined 3, francs , but the Court of Appeals released him. Vidocq is credited with having introduced record-keeping, criminology , and ballistics to criminal investigation. He made the first plaster casts of shoe impressions.
He created indelible ink and unalterable bond paper with his printing company. His form of anthropometrics is still partially used by French police. He is also credited for philanthropic pursuits β he claimed he never informed on anyone who had stolen for real need.
Field became a friend of Charles Dickens , and the latter wrote articles about him. In , one of his employees, the Hungarian Ignatius Paul Pollaky , left him and set up a rival agency. Although little-remembered today, Pollaky's fame at the time was such that he was mentioned in various books of the s and immortalized as "Paddington" Pollaky for his "keen penetration" in the comic opera, Patience. Pinkerton became famous when he foiled a plot to assassinate then President-elect Abraham Lincoln in Pinkerton's agents performed services which ranged from undercover investigations and detection of crimes, to plant protection and armed security.
