Legal Definitions - criminalistics

Criminalistics refers to the application of scientific principles and techniques to analyze physical evidence found at crime scenes or related to criminal investigations. It is the scientific discipline focused on identifying, collecting, preserving, and examining physical evidence to help solve crimes, reconstruct events, and link suspects to criminal acts. Criminalistics involves laboratory analysis across various forensic specializations, such as DNA analysis, fingerprint examination, ballistics, trace evidence analysis, and forensic toxicology.

• Scenario: A suspected arson at a commercial building.
  Criminalists specializing in fire debris analysis would collect samples of charred materials, soil, and other residues from the scene. These samples are then subjected to laboratory tests, such as gas chromatography-mass spectrometry, to detect and identify any ignitable liquids (like gasoline or kerosene) that might have been used to start the fire. This scientific analysis of physical evidence helps determine if the fire was accidental or intentionally set.
• Scenario: A hit-and-run accident where a pedestrian was injured.
  Investigators find small fragments of paint and plastic at the scene. Criminalists would analyze these fragments, using techniques like microscopy and spectroscopy, to determine their color, layers, chemical composition, and even manufacturer. This detailed examination of the physical evidence helps narrow down the make and model of the suspect vehicle, providing crucial leads for law enforcement.
• Scenario: A burglary where a safe was forcibly opened.
  Police recover tools suspected of being used in the break-in from a suspect's garage. Criminalists specializing in tool mark analysis would compare the unique striations and impressions left on the safe with test marks made by the recovered tools. Through microscopic examination and comparison, they can determine if the suspect's tools were indeed the ones used to force open the safe, establishing a physical link between the suspect and the crime.