Private Investigator has been used to know details of people or person, especially at the time of marriages. The need to know whether the bride or the groom are suited for each other, enforce the need for checking their backgrounds respectively. They are also used in cases of marriages that have already taken place to check the fidelity of the spouses concerned. Lawyers have been known to use their services in divorce cases.
See also: Private Investigator, Screen Saver, Internet Explorer Add on