Forensic scientists examine the physical evidence gathered at crime scenes to help determine the nature of a crime and if there is any evidence indicating who committed it. Much of forensic science is dependent upon chemistry and the analysis of chemical compositions, but what is lesser known is how the forensic scientist makes use of physics in his regular investigation of crime evidence.
Science Used in Forensics
Forensic scientists need to have a strong grounding in many different fields of science and must understand how they interrelate to one another. According to the Bureau of Labor Statistics, forensic scientists need to have a strong grounding in both math and science and should obtain either an associate's or bachelor's degree in some field of science. Degree programs should be heavily steeped in laboratory work and hands-on application of science like physics.
Another important use of physics in the work of the forensic scientist is in the study of ballistics. Ballistic evidence can sometimes be used to determine the trajectory of a bullet and its potential impact on the item it strikes, whether it be a person or an object. Forensic scientists need to understand how force and trajectory impact an object that is struck. Understanding different projectiles and their potential impact makes it possible to understand what weapon was used and from where it was used as well.
Another way in which the discipline of physics is important for the forensic scientist to know is in the analysis of evidence that is too microscopic to analyze through chemical analysis. According to an article by T.J. Wilkinson, et. al., in a 2002 issue of "Physics World," forensic scientists make use of infrared spectromicroscopy as a means of investigation for microscopic particles. This scientific technique involves using infrared photons to determine a particle's vibrational mode. Since different substances have unique vibrations, forensic scientists can use this information to analyze crime scene evidence.
Crime Scene Reconstruction
Crime scene reconstruction is heavily dependent upon the discipline of physics. Crime scenes often appear to be a chaotic mess of evidence. Crime scene investigators can use physics, however, to understand exactly how a crime took place. In some cases this is through ballistics analysis, but there are often more factors to consider than just the trajectory of a bullet. Instead, blood splatter analysis can be used to determine useful information about the crime as can the the other evidence found at the scene. If a struggle ensued, physics can help indicate the severity of the struggle. In crimes where multiple perpetrators are present, but not evidently so, physics can help reveal this to be the case based on the crime scene reconstruction.