Evidence Collection - YIPI 2023 PDF

INVESTIGATION AND EVIDENCE Evidence Collection  Session Objectives  Understanding evidence continuity.  Preparing evidence labels.  Collecting and packaging blood, hair and fibers, semen, saliva, cigarette butts, paint, gases, soil, and fingerprint evidence. What do you do?  Purpose of p...

INVESTIGATION AND EVIDENCE Evidence Collection  Session Objectives  Understanding evidence continuity.  Preparing evidence labels.  Collecting and packaging blood, hair and fibers, semen, saliva, cigarette butts, paint, gases, soil, and fingerprint evidence. What do you do?  Purpose of proper evidence collection is to protect the evidence from being contaminated.  Two important points in evidence collection 1. Proper packaging to maximize integrity. 2. Evidence continuity. Evidence Continuity Continuity of Exhibits  Establishing a continuous unbroken documented chain of custody from the discovery of an exhibit to its tendering in court, and the final disposition of the item. Continuity of Exhibits  Each and every movement of the exhibit  Officer contact  Lab submissions  All to be documented with the;  time, date, and who handled the item. Continuity of Exhibits  If the chain is broken at any point Defence a may argue the value of the evidence.  Cases involving the potential for large numbers of exhibits, consider assigning an exhibits officer to manage all items.  Consider property or exhibit management software / Computer at the scene Evidence Continuity  When evidence is passed from one person to another person difficulties arise.  Initialing evidence is essential.  Use evidence labels.  Use evidence seals.  Wear latex gloves. Evidence Labels  Use evidence labels.  Ensure, date and time, the location, what the evidence is and who located the evidence, is on the label. Evidence Seals  Provides evidence continuity and integrity. Evidence Collection and Packaging The manner of collecting and preserving physical evidence at a crime scene is determined by the nature of the evidence. Evidence Packaging  A cardboard box, plastic bags or plastic vials, paper bags or envelops can be used to package evidence.  Once packaged secure with an evidence seal and attach an evidence label.  Do Not Lick the envelope glue!!! DNA Comparison Samples (Victim or Suspect)  Blood Sample (DNA Collection kit) RCMP standard  Oral buccal swab  Hair – pulled with root sheath* onto clean new paper – Druggist fold Collecting Blood  Identification of ABO blood grouping Old method - Now DNA.  Use latex gloves.  Wet blood - use a dry sterile swab scrub target area.  Dried blood - moisten a sterile swab with distilled/sterile water and scrub into the blood. Collecting Blood  If you take a comparison swab take from an from adjacent area.  Place evidence information directly on swab container with an indelible marker.  Maintain a sample of the water used to moisten swabs.  Blood on clothing - collect the entire object.  Clothing should be air dried and not placed in an airtight container  Whole blood must be refrigerated or Heparin used (a blood preservative). Collecting Hair and Fibers WHY?  Determine if hair is human or animal, gender and area of the body.  Determine the type of fiber, colour match and origin. Linkage between suspect and scene. HOW?  With a clear broad tape “similar to packing tape” over finger tips, pat target surface.  Sandwich tape between two plastic sheets to protect evidence. *Whole exhibit can be submitted when possible Note – The lab will transmit light through the sample to find minute fibres Collecting Hair Comparison Samples For DNA Analysis:  Hair comparison samples  At least 10-15 pulled scalp or pubic hairs with root sheaths.  Hair: package into a folded paper (Druggist’s Fold) and place in an envelope. Label envelope and seal * Do not Lick. Collecting Hair for Conventional Analysis – Comparison Sample  Scalp: 10-15 plucked and fallen hairs  Pubic Hair: approximately 10-15 pubic hairs, pulled and / or combed  Body Hair: minimum of 10-15 body hairs, pulled and or combed from areas of interest  All hair samples should have the root sheath for best results Collecting Fibre Comparison Samples  The entire item that may have transferred fibres eg: clothing, rug, blanket, pillows Or  Cut out an area large enough to provide a representative sample of the item  Package individually and properly Label Keep Separate from other samples transport and submit Collecting Semen and Saliva WHY?  Determine source and identify DNA  Semen fluoresces under ultra violet light.  Collect and dry object with suspected semen  Package properly, likely 1st wave of CFS submissions Collecting Semen and Saliva  Cigarette butts can be used to determine ABO grouping or DNA  Air-dry samples, and package in plastic bag, container or envelope.  Initial, label and seal the container. *Remember to submit comparison sample from victim or suspect (buccal swab or blood) Collecting Paint  Paper Druggist fold  Use four fold paper.  Secure top of paper under paint sample.  Using sharp utility knife, scrape paint into folded sheet of paper.  Initial, label and seal sheet in envelope. *can also use glass or plastic containers Collecting Gases / Air Sample  Identify type of gas.  Fill glass jar with water.  Empty water filled jar into empty jar and seal with proper lid to now empty jar while holding jar upside down - close to pungent volatile liquid source.  Initial, label and seal glass jar. Collection of volatile material, Fire Debris Collecting Soil  Determine origin.  Use small plastic vials.  Collect samples in four different directions to a distance of 50 feet.  Initial, label and seal plastic vials. Collecting Knives or Firearms  Suitable for fingerprints.  Identification of spent bullets.  Handle the item were you normally would not handle the item. (Consider sliding a cardboard sheet under the item and submitting the item with the sample). Why Cardboard or similar material?  Do not place pencil in firearm barrel.  Do not place in plastic bags*. Collecting Knives or Firearms  If possible do not package weapon, hand deliver.  Package in a manner which weapon is supported and movement is stabilized.  Indicate the Pointed end on the outside of the container.  Label and seal. Collecting Beer Bottles for Fingerprinting  Suitable for fingerprints.  Handle in location were fingerprint are unlikely to be.  Package in paper envelope or bag.  Consider bottle carrier (isolates each bottle)  Anything potentially ‘wet’ should be packaged in paper/cardboard container. Collecting Clothing  May hold semen, fibers, blood etc..  Package in paper bag (ensure dry)  Initial, label and seal.  Exception: Clothing for Volatile Ignitable Liquids – do NOT air dry  Mason Jar / Nylon Bag