9781422273463

or disprove others. It can solidify a timeline or support an alibi. It can give investigators a clearer picture of what happened when, where, and by whom. Sometimes, a piece of evidence merely gives investigators a new lead to follow or reveals that a lead they’re chasing is a dead end. Other times, that impression left behind at the scene of the crime may be the piece of evidence that, when presented in court, convinces the jury of a particular verdict. Because impression evidence is valuable within the criminal justice world, forensic scientists must have the right skills, knowledge, and tools to properly collect, record, analyze, and interpret it. They initially develop their skills through adequate education and on-the-job training and then continue to build on and expand their knowledge base throughout the course of their career. As technology and science evolve, new opportunities may also emerge within the field of forensic science. On the Job: Forensic Scientists Forensic scientists or technicians may encounter or deal with impression evidence during the process of searching a crime scene. More often, however, they will specialize in a particular area. For example, there are forensic fingerprint experts and tool mark examiners who specialize in that specific type of evidence and will be called to a crime scene if those kinds of impressions are detected. “Forensic science,” or “criminalistics,” is the general term for the application of various scientific principles and techniques to the criminal justice world—particularly relating to the collection, examination, and analysis of physical evidence from crime scenes. Across literature and in the field, forensic scientists may also be referred to as “criminalists,” “forensic analysts,” “crime scene investigators,” or “lab techs.” More specific terms become applicable if a forensic scientist pursues a particular subdiscipline, such as pathology, toxicology, or fingerprint identification. For example, all forensic toxicologists are forensic scientists, but not all forensic scientists are forensic toxicologists. In general, all forensic scientists must acquire at least a bachelor’s degree from an accredited college or university. Optimal fields of study for individuals who want to become experts in a category of impression evidence include physical or natural sciences, criminal justice, biological sciences, or forensic science. However, fingerprint analysts and forensic footwear and tire tread examiners may also use chemical treatments to aid in the discovery and analysis of prints. The American Academy of Forensic Sciences encourages students who are interested in careers as forensic analysts to study a range of topics, including math, chemistry,

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Impression Evidence