Empirically-Based Evidence Plays a Crucial

Empirically-based evidence plays a crucial role in the administering of justice in the legal system, particularly as it relates to investigative psychology. There has been a plethora of evidence gathered that indicates other aspects of forensic psychology, such as eye-witness reports, are suspect, subjective, and not always accurate. Therefore, it is necessary to utilize testimony from experts in forensics and psychology that is rooted in fact. The most efficacious method of determining fact is to utilize scientific methods, of which empirical evidence -- meaning that which can be demonstrated or proven -- plays a huge part.

Moreover, there is a history of success in criminal cases in which forensic psychologists either testified or concurred with law enforcement officials regarding the culpability of a particular suspect based on external scientific evidence. An excellent example of this fact is found in the case of Thomas Dillon, a young man who was accused of sniping and murdering a number of fishermen, hunters, and joggers in Ohio near the turn of the 21st millennium. In this particular case, investigators were able to put together a composite overview of certain qualities that the purported killer had. This description was able to be validated by a forensic psychologist, a fact which played a significant role in the subsequent surveillance and eventual arrest and charge of Dillon to murders in this case. This confirmation, "What you have is a hunter of humans," said a noted forensic psychiatrist who has been involved in such celebrated cases as Ted Bundy and Jack Ruby (Knox et al., 1993), is pivotal to the determining of murder suspects and possible convictions.

The allusions in the preceding quotation to other notorious criminals and murder trials including the likes of Bundy and Ruby only attest to the increasing reliance of the criminal justice system on the valuations of forensic psychologists. As such, it is increasingly importance that these professionals base their judgments on objective, scientifically validated principles and methodologies -- especially when it makes the difference between the life and death of a human being, and the rendering of justice for those who may have been violated by such a person.

Thus, the relationship between investigative psychology and forensic psychology is fairly lucid. Investigative psychology largely provides the means of identifying suspects and eventually indicting them. The mechanics of investigative psychology are multi-fold. For instance, in the case of the so-called "D.C. Sniper" in 2002, investigators were able to gain forensic evidence regarding ballistics and fingerprints. The former enabled them to identify the type of weapon that was repeatedly used during the attacks; the latter was used to procure a suspect in this particular case (Federal, 2007).