The Federal Bureau of Investigation, perhaps one of the highest profile law enforcement agencies in the world, has specific requirements for candidates to be an investigator or special agent. A potential agent must have three years law enforcement work experience and a four-year degree from a fully-accredited U.S. college or university with a study major or background in accounting, information technology, computer science, language or law. The entry skills are further divided into a dozen priority skills ranging from intelligence experience to tactical operations/special forces training. Once accepted, candidates must succeed in the 20-week course at the FBI Academy in Quantico, Virginia. The training consists of 850 instructional hours that include academics, case studies, firearms, operational skills -- handcuffing, boxing, controlling suspects-- and physical training.
While virtually all positions in law enforcement require U.S. citizenship and a background check, requirements to be a law enforcement investigator at the state level vary. For example, in California, to be accepted for training as a special agent in the Department of Justice, a candidate needs some law enforcement background and one or two years of college. California also requires a written test and essay as well as a series of examinations such as a physical and a polygraph and completion of a law enforcement course. The Texas Rangers, the oldest statewide law enforcement agency in North America, is even more exacting. Beyond specific work experience, applicants must hold a two-year degree or have 90 semester hours at an accredited college or university. Military experience can be substituted for some of the educational requirements.
The largest law enforcement agency in Colorado, the Denver Police Department requires candidates to have proof of a high school diploma or GED and about six months of intense instruction at the Denver Police Academy. The Milwaukee Police Department requires a two-year degree from a community or technical college. In both cited departments and in most others, the opportunity to become an investigator or detective comes with experience as a police officer and results in a promotion, perhaps to detective or to a specialized area of policing.