Crime Scene Investigation Quiz Pt.2

Crime Scene Investigation Procedures

• Rigor mortis begins at the neck and lower jaw and spreads downwards, starting 5 to 6 hours after death, affecting the whole body within about 18 hours, and disappearing within thirty-six hours.
• Body temperature, influenced by air temperature and clothing, can help determine the time of death.
• Putrefaction, the decomposition of body tissues, is influenced by environmental temperature and can aid in approximating time of death.
• Cadaveric spasm, immediate stiffening in small muscles of the face and/or hands, can strongly indicate suicide if the hand is clutching a weapon.
• Upon arrival at a crime scene, officers should determine the presence of suspects, weapons involved, and request backup if necessary.
• Procedures for identifying victims in the case of serious injury or death involve obtaining identification and information about next of kin.
• Special units that may be called to the scene include EMS, Medical Examiner/J.P., bomb squad, fire department, military, narcotics investigators, and other law enforcement agencies.
• Information about suspects, clothing, vehicles, weapons, and direction of travel should be made known to other officers.
• Legal authority to protect the crime scene and establish perimeters is granted to peace officers and medical examiners.
• Procedures for securing the crime scene include establishing entry and exit points, inner and outer perimeters, and protecting the scene from contamination and evidence removal.
• The objectives of conducting a crime scene search include establishing that a crime has been committed, placing the suspect at the scene, eliminating persons through DNA testing, and supporting witness testimony with physical evidence.
• Potential problems in conducting a crime scene search include evaluating physical characteristics of the area to be searched, such as size, landscape, and indoor vs. outdoor settings.

Crime Scene Search and Documentation Procedures

• Implementation procedures for crime scene searches include determining the starting point based on priorities, establishing a headquarters, conducting a briefing, assigning areas of responsibility, and maintaining communication with all searchers.
• The basic steps of a crime scene search typically involve approaching the scene, securing and protecting it, conducting a preliminary survey, documenting evidence, and collecting evidence while establishing chain of custody.
• Additional investigative and technical personnel should be called when one person cannot search the area, there is an impractical amount of damage or evidence, or expertise beyond those present is needed.
• Evidence may be used in criminal actions based on specific legal criteria, and procedures for photographing a crime scene include preparation, maintaining a log of photos, and taking photographs from three major vantage points: overall, mid-range, and close-up.
• Specific documentation requirements exist for sexual assault, child abuse, and family violence cases, and there is mandatory training for these documentation procedures.
• Crime scene sketches serve to provide a permanent record of conditions not easily recorded by photography, help reconstruct the crime scene, and corroborate witness testimony.
• Proper procedures for crime scene documentation include methods of measurement such as triangulation and documenting the location and spatial relationships between pieces of evidence and the surroundings.