Seven S's of Crime scene investigation
Securing and collecting evidence
All evidence needs to properly packaged, sealed, and labeled. Specific procedure and techniques for evidence collection and storage must be followed. Liquids are placed in airtight containers Moist evidence are aired out, reducing mold contamination ---> placed in bindle Evidence log and chain of custody doc must be attached to the evidence container.
Sketching the scene
An accurate rough sketch of the scene is made, noting position of body and any other evidence. All objects should be measure from two immovable landmarks. On sketch, north should be labeled and scale provided. Any other objects in vicinity should be included in sketch (doors, windows, and furniture). If outdoors, position of trees, vehicles, hedges, and other structures should be include. Later, a more accurate final copy should be presentable at court.
Seeing the scene
Crime scene examiners see the scene. Photos of overall area and close ups should be taken. Triangulation of stationary objects should be included in the photos as reference points. View should be taken at different angles and distances, close ups of evidence and bodies should be taken.
Scanning the scene
Forensic examiners then scan the scene to determine where photos should be taken. Determination of Primary crime scene and secondary crime scene and priorities assigned regarding examination.
Searching for evidence
Depending on number of investigators, a spiral, grid, linear, or quadrant pattern should be walked and location of evidence marked, photographed, and sketched. Single investigators might use a grid, spiral, or linear pattern. A group might use a linear or quadrant pattern.
Separating the witnesses
Next priority. Witness are not allowed to talk with one another. Separation avoids witnesses to work together to create a false story (collusion). Questions asked: -when did the crime scene occur? -Who called in the crime? -Who is the victim? -can the perpetrator be identified? -What did you see happen? -Where were you when you observed the crime scene?
Securing the scene
responsibility of the first-responding police officer (first responder), safety of individuals is first priority. Preservation of evidence is second priority. First responder has to restrict all unauthorized persons from entering. Locard's exchange principle may occur. -first responder keeps security log of all those who visit the crime scene -may call more teams of experts to sent to scene