Crime Scene Investigation
Welcome To Real World CSI
Welcome to the All About Forensic Science website crime scene investigation pages. From here you will be able to access comprehensive information relating to all aspects of crime scene investigation. Including:
The following information was produced by The U.S. Department of Justice.
Responding to a crime-scene is a critical step in the scientific investigation of a case. Unless the crime-scene response is handled correctly, the investigation may be severely compromised. Crime-Scene investigators and crime-scene specialists are responsible for identifying, securing, collecting, and preserving evidence which is submitted to the crime laboratory.
The investigator's knowledge in crime-scene documentation and the variety of methods for the collection and processing of all types of evidence is crucial. In addition, the investigator must often make timely decisions whether to obtain written consent or a search warrant, so that the evidence will be admissible and not subject to a motion to suppress.
Types of Evidence
TESTIMONIAL: Statements or the spoken word from the victim(s) or witness(es).
PHYSICAL: "Real evidence", refers to such things as hairs, fibers, latent fingerprints, and biological material.
Locard's Exchange Principle
Crime scene concept which states that every time someone enters an environment, something is added to and removed from it. The notion that "every contact leaves a trace," applies to contact between individuals as well as between individuals and a physical environment. Crime-scene investigators are taught to assume that physical evidence will be left behind, the amount and nature of this will largely depend on the circumstances of the crime.
Examples of Evidence Left Behind at A Crime-Scene
Physical Evidence: The Silent Witness
Evidence often tells a story and helps crime scene investigators re-create the crime scene and establish the sequence of events. Physical evidence can corroborate statements from the victim(s), witness(es) and/or suspect(s). If analyzed and interpreted properly, physical evidence is more reliable than testimonial evidence; testimonial evidence is more subjective in nature.
An individual's perception of events and memory of what happened can be incomplete or inaccurate. Physical evidence is objective and when documented, collected, and preserved properly may be the only definitive way to reliably place or link someone to a crime scene. This is why Physical evidence is known as the "silent witness."
Click on the links below for information about various aspects of crime scene investigation.
USA Forensic Science Programs Search