NOCTI Test Study Guide 1 ‘Crime Scene Management • Exhibit understanding of proper evidence collection practices o Procedure for collecting evidence ▪ All material gathered during a criminal investigation must be carefully collected, recorded, classified, processed, and stored ▪ All evidence must be marked for identification and protectively packaged ● If officers fail to follow proper procedures the “chain of evidence” may be broken, tainting evidence and making it inadmissible in court o Chain of Evidence Sequence ▪ Identification and collection ▪ analysis ▪ storage ▪ Preservation ▪ Transportation ▪ presentation in court ▪ return to owner ● The chain of evidence shows o who obtained the evidence o where and when the evidence was obtained o who secured the evidence o who had control or possession of the evidence • Exhibit knowledge of scientific principles involved in crime scene management o Four components of a crime scene ▪ Information management ● Information can: link a suspect to a crime scene, approve or disapprove an alibi, or develop investigative leads ● Can be in oral form, written statements or documents, or patterns ● Various types of information can be used to solve crimes o Comprehensive victim background check o Inquiry into the suspects whereabouts and belongings within the past 24 hours of the proceeding crime ▪ Manpower management ● The agencies responsible for the crime scene processing and construction ● Factors of manpower management that affect crime scene management o Insufficient personnel NOCTI Test Study Guide 2 o Poor training and lack of experience o Overworked crime scene team ▪ Technology management ● Money allocated for purchasing and updating equipment should be should be adequate to the variety of crime scenes encountered by the team/unit ● Adequate training to personnel to properly utilize new technology and equipment o Categories of equipment ▪ Support vehicles ▪ Communication- two way radio, computer ▪ Tools and search equipment- metal detectors, forensic light tools ▪ Specialized crime scene kits- latent print kits ▪ Chemicals and reagents-blood print enhancement reagent, latent print developers ▪ Portable instrumentation-portable laser, night vision equipment ▪ Evidence packaging materials and related forms ▪ Management of logistics ● Logistical concerns should be properly addressed through good planning, organization, and efficient distribution of resources- to be established earlier in the investigation o Elements to be established ▪ Command posts ● A command post should be situated outside the perimeter of the working crime scene away from the evidence location ▪ Media relations ● Care should be taken to restrict access to the crime scene and a separate area should be identified for members of the public and media ▪ A shortage in one of these areas, or an over emphasis of a component will result in a system that is out of balance and that will jeopardize the overall management of the crime scene investigation process • Exhibit understanding of proper evidence preservation practices o Proper evidence preservation ▪ The preservation of all items of physical evidence relating to felony crimes, regardless of whether an individual files a petition for postconviction DNA testing. NOCTI Test Study Guide 3 ▪ The retention of crime scene evidence that is associated with unsolved cases. ▪ The retention of all items of physical evidence secured in connection with a felony for the period of time that any person remains incarcerated, on probation or parole, involved in civil litigation in connection with the case, or subject to registration as a sex offender. ▪ Provisions enabling courts to determine the appropriate remedy when evidence is improperly destroyed. ● Procedures for collecting evidence (examples) o Secure the scene o Liquid pools of blood should be absorbed with a gauze pad and frozen or refrigerated asap o Hair should be picked up with tweezers and stored in a paper bindle or coin envelope then labeled o In rape cases the pubic region should be combed prior to collecting standards (30-60 pubic hairs are required). Obtain hair samples from the victim, suspect, and any other possible sources for comparison. Have the victim and suspect bend over a large sheet of white paper and rub their hands through their scalp so loose hairs will fall out. (50- 100 hairs are desired) o Wrap recovered bullets in paper and seal in a separate, secure pill box or envelope • Exhibit understanding of initial crime scene management o Note taking o Securing the crime scene ▪ Locking down the crime scene ▪ Setting up crime scene perimeters ▪ Establishing a path of contamination ▪ Establishing crime scene security o Evidence management o Scaling the investigation to event • Identify and/or perform latent print techniques o Latent print ▪ Impressions produced by the ridged skin, known as friction ridges, on human fingers, palms, and soles of the feet. o Technique Examples ▪ Powders ● Adhere to both water and fatty deposits. ● Useful on newer prints only. ● They’re useful on any dry, relatively smooth, non-adhesive surfaces. ▪ Silver nitrate NOCTI Test Study Guide 4 ● Reacts with the chlorides in skin secretions to form silver chloride, o A material which turns gray when exposed to light. ● Developed prints must be photographed immediately because the reaction will permanently fill the background. ● Useful on paper, cardboard, plastics and unvarnished, light-colored woods. ● Not useful on items which have been exposed to water.