About 17 percent were self-employed. About 36 percent of wage and salary workers worked for detective agencies and about 42 percent were employed as store detectives in department or clothing and accessories stores. Others worked for hotels and other lodging places, legal services firms, and in other industries. Almost all private detectives and investigators have previous experience in other occupations. Some work initially for insurance or collections companies or in the security industry.
Many investigators enter the field after serving in military or law enforcement jobs.
Retired law enforcement officers, military investigators, and government agents frequently become private detectives and investigators as a second career. Others enter from such diverse fields as finance, accounting, investigative reporting, insurance, and law. These individuals often can apply their prior work experience in a related investigation specialty. A few enter the occupation directly after graduation from college, generally with majors in such fields as criminal justice or police science. The majority of the States and the District of Colombia require private detectives and investigators be licensed by the State or local authorities.