When a crime is committed, a profiler studies all the aspects of the crime or series of crimes in an attempt to understand the personality, behavior and motive of the perpetrator. This criminal profiling, combined with physical evidence, has had a lot of success in apprehending the criminal.

Police forces around the world, including the FBI, take these experts very seriously and value their input. There are some criminal psychologists however, who are skeptical about the effectiveness of such methods.

The first publicized account of a profiler at work was in the 1880s in England. The police were desperate to catch the so-called Jack the Ripper, a serial killer who had killed several prostitutes in a poor area of London. A police surgeon named Dr Thomas Bond laid the foundations for criminal profiling that are still followed today. Bond's contribution to the investigation was respected and there were suspects but the Ripper was never caught.

A number of steps are followed when profiling takes place. The profiler analyses the crime and forms an opinion as to whether there was prior planning or it was a spontaneous act and what could have motivated the action.

They will also look at the method of killing and the kind of victim that was selected. Another question is whether the body was disposed at the location of the murder or at another time. The behavior of the criminal after the crime has been committed and whether he or she attempts to goad the police or media can tell the profiler a lot about the personality of the perpetrator.

The concept of this skill has become very familiar to the public because of movies and TV shows that deal with criminal profiling. The most famous movie on the subject is the Silence of the Lambs. Jodie Foster's character, an FBI agent, seeks advice on the identity of a serial killer from the notorious Hannibel Lecter.

He is able to point the FBI in the right direction. Another film, Copycat, stars Sigourney Weaver as a psychologist involved in criminal profiling, who must overcome personal trauma to catch a serial killer. The hit UK television series, Cracker, featured Robbie Coltrane as a flawed character who is brilliant at his job, gaining insight into the mind of killers. An American version, starring Robert Pastorelli, was shown but it did not live up to the standards of the original.