private investigator

investigator hired by private individuals, investigator that works independently

A private investigator, private detective, PI, or private eye, is a person who undertakes investigations, usually for a private citizen or some other entity not involved with a government or police organization.Private investigators often work for attorneys in civil cases or on behalf of a defense attorney. Many work for insurance companies to investigate suspicious claims. Before the advent of no-fault divorce, many private investigators were hired to search out evidence of adultery or other illegal conduct within marriage to establish grounds for a divorce. Despite the lack of legal necessity for such evidence in many jurisdictions, according to press reports collecting evidence of adultery or other "bad behavior" by spouses and partners is still one of the most profitable activities investigators undertake, as the stakes being fought over now are child custody, alimony, or marital property disputes.
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Private Investigator! is an adventure story arc of the Philippine comic strip series Pugad Baboy, created by Pol Medina Jr. and originally published in the Philippine Daily Inquirer. This particular story arc lasts 77 strips long and ran July to October, 2000, in the light of the then-recent bombings in some shopping malls. In 2001, the story arc was reprinted in PB the 13th, the thirteenth book compilation of the comic strip series. The story arc's title comes from the fact that every time Dagul's alter ego Bardagul Kapote's name is mentioned by the unseen narrator, he always follows it with the phrase "Private Investigator," which is what Bardagul Kapote is.
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Noun
1. someone who can be employed as a detective to collect information
(synonym) private detective, PI, private eye, operative, shamus, sherlock
(hypernym) detective
(hyponym) hotel detective, house detective, house dick