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The Classes and Characteristics of Evidence

hire forensic scientists to help process their heavy caseloads. Additionally, the BLS states that as technology and scientific methods evolve, and practitioners discover new ways to apply these practices to the criminal justice system, “the availability, reliability, and usefulness of objective forensic information used as evidence in trials” is expected to increase steadily. As a result, “forensic science technicians will be able to provide even greater value than before, and more forensic science technicians will be needed to provide timely forensics information to law enforcement agencies and courts.” may give them a different perspective when analyzing data. Circumstantial evidence is then sorted into other categories: physical, biological, reconstructive, or associative. Reconstructive evidence is anything that can help investigators get a better sense of what transpired at the scene during a crime—or in other words, reconstruct it. It deals with who did what, when, where, and how. Associative evidence is anything that links a specific suspect to the crime scene. It includes hairs, fibers, bodily fluids, footprints, paint, or weapons. Evidence will also bear class characteristics, or properties that place it in a group of objects. Better yet, some pieces of evidence possess individual characteristics, or properties that narrow down the source to a single person or a small group with relative certainty. There are several types of evidence utilized in the process of investigating and prosecuting crimes. To begin with, evidence is categorized as either direct or circumstantial. Direct evidence encompasses things like a confession from a perpetrator or a victim’s statement, which essentially establishes a fact. In contrast, circumstantial evidence is more objective data, although it doesn’t provide solid proof and must be interpreted by a judge or jury. Forensic scientists, including chemists, are more apt to deal with circumstantial evidence—fingerprints, hairs or fibers, bloodstains, drugs, or fire- starters—than direct evidence, although a witness or victim’s testimony

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Forensic Chemistry