Scientific Method and Criminal Investigator

Gathering information is the key to all good investigations, and so understanding the three sources of information is of great concern to any investigator. All of these items add up to a well-rounded and thorough investigation, and thus they will all be addressed herein. First, an exposition on the methods of inquiry are in order. The two overarching methods of inquiry are 1) those that reconstruct and examine past events and 2) those that discover or generate new information (Osterburg & Ward, 2010). These two are actually interrelated, and there is a good deal of overlap between them.

Any number of disciplines in both the hard and soft sciences can be employed in the service of an investigation, including those, which would not necessarily seem related to a police investigation, like entomology, meteorology, etc. Thus, understanding the behavior of insects that inhabit a body or the effects of weather on a body might provide crucial details about the precise date and time of a murder, for example. In fact, a wide array of disciplines is often applied to a complex investigation when used in conjunction, can provide a great deal of information about a case.

As well as utilizing the methods of inquiry, the best criminal detectives also generally approach a case with a particular mindset. In essence, the investigative mindset is part schema (innate perspective based on a broad knowledge of the world) and part active thought process. What it amounts to is an open-mindedness and (preferably unbiased) skepticism that allows the investigator to remain open to anything unusual in a case or anything that leads to a better understanding of the facts and circumstances—evidence—related to or surrounding a case (Osterburg & Ward, 2010).

The investigator with this mindset will therefore approach a case looking for evidence that seems contrary to how things should be according to his or her knowledge about the world and understanding of how things generally go under normal circumstances. She is also looking for information that fits what is already known about the case, but the investigator must be careful here not to come at it with preconceived notions about the guilt or innocence of anyone directly involved in or a tangential to the case.

For the gathering of evidence, the best approach is usually the application of the scientific method, defined as such: “a method of investigation in which a problem is first identified and observations, experiments, or other relevant data are then used to construct or test hypotheses that purport to solve it (Scientific method, 2009). ” The problem to be identified in this case is the investigator’s hypothesis about what took place at the crime scene and who was involved in it. Ergo, a good investigator moves from inductive reasoning—guesswork, hunches, suspicions, etc. toward deductive reasoning, which is the use of specific data applied to the situation to see if everything fits with what she believes to have happened. In Osterburg and Ward’s Criminal Investigation, the authors give an example in which a woman was murdered in her apartment in conjunction with a romantic dinner. Going on a hunch, the investigator suspects an ex-boyfriend to be the culprit. He then gathers data to see if his suspicions are reinforced by the facts available to him (Osterburg & Ward, 2010).

There are three sources of evidence that an investigator may draw from. The first of these is people. The relevant sources here are all of the people directly connected to a case (witnesses, suspects and of course surviving victims) and friends, relatives and various associates of suspects and victims (Osterburg & Ward, 2010). Although people can be open and helpful in a case, some of them may lie; distort facts or even refuse to cooperate altogether, creating a conflict for the investigator.

Witnesses may also be confused about what they actually observed as memory is not always reliable and can even be biased by personal, professional or societal schemas. Learning how to get people to cooperate with police and sorting out lies, half-truths, mistakes or previously overlooked information is essential to criminal investigation. Ongoing surveillance of the people involved may also shed light on a case. The second source for investigators to consider is physical evidence.

In police work, the two main disciplines employed in the examination of this data are forensic medicine and criminalistics. The condition, location and position of human remains; materials and fibers located at the crime scene; the trajectory of bullets and the type of bullets used; the pattern or spatter of blood; impressions made by fingerprints, shoes or tires; the presence of contraband (such as illegal drugs or drug paraphernalia or illegal weapons)—these are all types of physical evidence that might be used to reconstruct a crime or other past event (Osterburg & Ward, 2010).

In considering this evidence, the investigator will ask herself questions related to the crime, such as: What is this item doing here? Why is the blood pattern directed this way? Does this evidence support or contradict my hypothesis about a suspect? And so on. Finally, records and documents are a prime source of evidence for most investigations. Although technically records are physical evidence, they are a special form of physical evidence, in that they are in widespread use and are used, stored and accessed both privately and professionally specifically for their informational value.

It is no wonder then that they often contain or form important, highly specific evidence for an investigator. Documents such as a driver’s license, social security card or state ID card will help the police identify an unknown murder victim, for example. Criminal records of a murder victim may also provide clues about the nature of his murder, such as whether or not he was involved in the illegal drug trade, which may lead to a suspect. Phone records may even indicate that two people have been in contact when one or both have denied that they know each other (Osterburg & Ward, 2010).

Records may be stored as a hard copy on paper, plastic or some other medium, or they may be stored digitally, as on a computer hard drive or CD. In the end, it is apparent that science and a scientific perspective are highly important to police investigations. The two methods of inquiry provide a basis for understand what happened and how it happened. Encountering an investigation with the proper mindset will offer a higher success rate. In addition, of course, the application of the scientific method is indispensable, as is understanding and exploiting the three sources of evidence.