Hal Lipset
Hal Lipset was the most respected and also the sleaziest private detective in America. Lipset began as an investigator in the U.S. Army. Later he became a pioneer in electronic surveillance techniques (Coppola's movie The Conversation was partly a portrait of Lipset), while remaining busy with a variety of cases that range from standard divorce snooping through insurance fraud to catching a jewel thief in Europe. Lipset had an apolitical approach to his work: according to him, guilt or innocence is the court's concern, not his; he worked for anyone who paid.