Roy Hazelwood is a former FBI profiler of sex crimes and is generally regarded as the pioneer of profiling sexual predators. He worked for the Federal Bureau of Investigation but retired in the Early 90s. In 1980, he developed the distinction between "organized" and "disorganized" murderers, a concept that is still used by law enforcement to help in the apprehension of criminals. He also defined the four categories of rapists, which are power-reassurance, power assertive, … Wikipedia
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