Course Law Enforcement I. Unit XIV Crime Scene Search

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1 Course Law Enforcement I Unit XIV Crime Scene Search Essential Question What are the best procedures for protecting, processing and documenting a crime scene? TEKS (c) (15)(A)(B)(C) Evidence Collection Rationale As a law enforcement officer, students will be responsible for protecting, documenting and processing a crime scene. The student needs to learn the basic skills and procedures for collecting such important information from a crime scene. Objectives The student will be able to: 1. Define key terms 2. Explain the steps taken to thoroughly record a crime scene 3. Describe the proper procedures for conducting the systematic search of a crime scene for physical evidence 4. Identify types of physical evidence 5. Explore the proper techniques for collecting common types of physical evidence 6. Examine proper procedure for packaging common types of physical evidence 7. Understand the chain of custody concept 8. Lift and preserve developed latent prints from a simulated crime scene 9. Document and protect the crime scene area for further investigation 10. Demonstrate crime scene investigation techniques used to collect, protect, and document deoxyribonucleic acid evidence (DNA) in a simulated crime scene Prior Student Learning -Note taking/report writing -Ethics -Problemsolving Estimated Time 8 hours Engage Do an Internet search for a video about Techniques of Crime Scene Processing Part 2..View and discuss a video demonstrating evidence collection techniques. Use the Discussion Rubric for assessment. Key Points I. Key Terms A. Transient evidence evidence which will lose its evidentiary value if not preserved and protected (NIJ, 2009) B. Trace evidence physical evidence that results from the transfer of small quantities of material (NIJ, 2009) C. Physical evidence any object that can establish that a crime has been committed, or that can link a crime to its victim or perpetrator D. Crime Scene Search a planned and coordinated, legal search of a crime scene to recognize, preserve, and collect physical evidence that is related to the crime under investigation E. Crime Scene Sketch a drawing which represents the crime scene and serves to supplement photography by providing accurate information concerning the distance between various points in the 1

2 scene (TCLOESE, 2008) F. Evidence anything that helps establish the facts related to a crime (TCLOESE, 2008) G. Property 1. Something that is owned 2. Different types of property are a) Lost and found b) Seized c) Stolen d) Recovered H. Chain of Custody the process which reports transactions of evidence from person to person, starting with its acquisition by a law enforcement agency II. Recording the Crime Scene investigators have a limited amount of time to work a crime scene in its untouched state. The scene must be recorded in its original state. A. Crime Scene Sketching 1. Sketches are helpful in reconstructing the crime scene 2. Sketches record the exact locations and spatial relationships of pieces of evidence and surroundings of the crime scene 3. Three types of sketches are a) Field sketch b) Final report diagram c) Courtroom presentation 4. When measuring a crime scene, use an accurate measuring device 5. Obtain a sufficient number of measurements to accurately represent the crime scene and its contents 6. Establish permanent reference points to measure from and record the measurements on a crime scene sketch 7. Two types of surveying methods a) Triangulation measurements are made from two or more fixed reference points to intersect at the location of the object or item of evidence b) Rectangular Coordinates measurements of objects or items of evidence are located using two perpendicular lines at right angles 8. The title block of the sketch contains a) Case number b) Offense location c) Date of the offense d) Name of the person diagramming the scene e) North directional indicator f) The words not to scale 9. Four methods used to sketch a crime scene area 2

3 a) Schematic Sketch (aka Flat Sketch) (1) Used for most field sketches (2) Used when it is desirable to represent an orderly combination of events b) Perspective Sketch (aka 3-D) drawn in such a way to show the scene as it would appear to the eye with a reference to relative distance or depth c) Projection Sketch (aka cross projection) (1) Said to be the most frequently used sketch (2) Used when it becomes necessary to portray the correlation of evidentiary facts at the scene d) Detailed Sketch used for more specific drawings such as cylinder diagrams, damage to door frames at the point of entry on a burglary, or injuries to the victim of an assault B. Photographing the scene 1. The photographic ID card a) The first photograph taken on each and every series of pictures b) Contains the following information (1) Case number (2) Location where the photos were taken (3) Time the photos were taken (4) Name and ID number of the person taking the photos 2. Objects a) Not to be moved until they are photographed from all necessary angles, unless the crime involves an injured person b) Photographed when they are discovered, to show their position and location in the entire scene 3. Close-ups should be taken to record the details of objects; a ruler or other measuring scale may be inserted near the object and included as a point of reference 4. The crime scene should include the area in which the crime took place and all adjacent areas 5. Overview photographs of the entire scene and surrounding area, including points of exit and entry, must be taken from various angles 6. Close-up photographs depicting injuries or weapons lying near the body must be taken 7. The surface beneath the body should be photographed after the body has been removed from the scene C. Crime Scene Notes 1. Note-taking must be constant and precise throughout the investigation 3

4 2. The scene, location of evidence, time said evidence was collected and by whom, etc. must all be documented in detail 3. Detailed descriptions will help the investigator call to mind evidence when presented with it at a later date, such as when a case is reopened or goes on trial III. Crime Scene Search Methods A. Prior to starting a crime scene search, the following must be completed: 1. Determine a starting point 2. Establish a headquarters or command post 3. Brief your searchers 4. Discuss and establish the speed of the searchers 5. Assign an area of responsibility to each person in the search group 6. Maintain communication among all searchers 7. Recheck the search area by exchanging searchers from one area to another B. When determining which search method to use, consider the following: 1. The size and type of the area to be covered 2. The personnel and equipment needed 3. The degree of thoroughness required depending upon the type of crime committed, the type of evidence to be collected, and the purpose of the search C. Types 1. Zone Search a) The officer in charge divides the crime scene into sectors and each team member takes one sector. Team members may then switch sectors and search again to ensure complete coverage b) Effective for both indoor and outdoor searches which have regular patterns and defined borders c) Allows for different types of searches within each of the quadrants 2. Outward Spiral Search a) The officer starts at the center of the scene (or at the body) and works outward b) Useful when an item is missing from the center and the search must be conducted rapidly c) May begin inside or outside as the circumstances dictate 3. Inward Spiral Search a) The officer starts at the perimeter of the scene and works toward the center. b) Spiral patterns are a good method to use when there is only one officer at the scene 4

5 4. Point-to-Point a) A preliminary step in evaluating the scene b) Some of the disadvantages are (1) Can be disorganized (2) Trace evidence may be overlooked (3) Others at the scene may feel that when this method of search is completed, they are free to enter the scene, so they might move items of evidence 5. Strip Search Parallel (Line) Search a) All members of the team form a line; then they walk in a straight line, at the same speed, from one end of a crime scene to the other b) It may be used in single or double forms c) It is among the most effective for outdoor searches 6. Area Search a) An area (grid) search is simply two sets of parallel searches offset by 90 degrees and performed one after the other b) This search uses any technique which will be effective in examining specific and small areas with defined borders, such as (1) Bushes (2) Pathways (3) Sidewalks/driveways IV. Types of Physical Evidence A. Bodily fluids B. Blood C. Hairs and fibers D. Fingerprints E. Footwear impressions F. Tool marks G. Firearms H. Documents I. Any other item linking a suspect to a crime V. Collecting Evidence A. Trace Evidence 1. Includes gunshot residue (GSR), paint residue, chemicals, glass, and illicit drugs 2. Collection may be done with tweezers, plastic containers with lids, a filtered vacuum device, and/or a knife 3. Officers will also have a biohazard kit on hand that contains disposable latex gloves, booties, a face mask and gown, and a biohazard waste bag 4. Technicians discover a lot of the trace evidence for a crime in 5

6 the lab when they shake out bedding, clothing, towels, couch cushions, and other items found at the scene 5. The technicians shake out the items in a sterile room onto a large, white slab covered with paper B. Bodily Fluids 1. Bodily fluids found at a crime scene might include blood, semen, saliva, and vomit 2. To identify and collect these specimens of evidence, an officer/csi might use smear slides, a scalpel, tweezers, scissors, sterile cloth squares, a UV light, protective eye wear, and/or luminol 3. Officers will use a blood collection kit to get samples from any suspects, or from a living victim, to use for comparison C. Blood 1. If the victim is dead and there is blood on the body, the officer/csi collects a blood sample, either by submitting a piece of clothing or by using a sterile cloth square and a small amount of distilled water to remove some blood from the body 2. Blood or saliva collected from the body may belong to someone else, and the lab will perform a DNA analysis so the sample can be used later to compare to blood or saliva taken from a suspect 3. The officer/csi will also scrape the victim s nails for skin; if there was a struggle, the suspect s skin (and therefore DNA) might be under the victim s nails 4. Blood spatter patterns can reveal a) The type of weapon used b) The number of blows c) A cast-off pattern D. Hair and Fibers 1. The officer/csi may use combs, tweezers, containers, and/or a filtered vacuum device to collect any hair or fibers at the scene 2. In a rape case with a live victim, the officer accompanies the victim to the hospital to obtain any hairs or fibers found on the victim s body during the medical examination 3. The officer seals any hair or fiber evidence in separate containers and transports it to the lab E. Fingerprints 1. Tools for recovering fingerprints include brushes, powders, tape, chemicals, lift cards, magnifying glasses, and super glue 2. A crime lab can use fingerprints to identify the victim or to identify or rule out a suspect 3. There are several types of prints an officer might find at a crime scene: a) Visible left by the transfer of blood, paint, or another 6

7 fluid or powder onto a surface that is smooth enough to hold the print; evident to the naked eye b) Molded left in a soft medium such as soap, putty, or candle wax, forming an impression c) Latent left by the transfer of sweat and natural oils from the fingers onto a surface that is smooth enough to hold the print; not visible to the naked eye F. Footwear Impressions and Tool Marks 1. A footwear impression in mud or a tool mark on a window frame is an example of a three-dimensional impression 2. If it is not possible to submit the entire object containing the impression to the crime lab, an officer/csi makes a casting at the scene G. Firearms/Weapons 1. Types of firearms/weapons evidence include knives, guns, bullet holes, and cartridge casings 2. Forensic scientists can a) Recover serial numbers b) Match bullets and casings to (1) The firing weapon (2) Evidence from other crime scenes (a) Bullets (b) Casings 3. Bullet hole analysis a) Cut out a portion of the wall or frame b) Do not dig bullets out of the victim or other objects c) Can determine where and from what height the bullet was fired d) Position of the victim when it was fired e) A laser trajectory kit is used H. Documents 1. An officer/csi collects and preserves any diaries, planners, phonebooks, or suicide notes found at a crime scene 2. The officer/csi also delivers to the lab any signed contracts, receipts, torn up letters, or any other written, typed, or photocopied evidence that might relate to the crime 3. A documents lab can often reconstruct a destroyed document, even one that has been burned, as well as determine if a document has been altered 4. Technicians analyze documents for forgery, determine handwriting matches to the victim(s) and suspects, and identify what type of machine was used to produce the document 5. They can rule out a printer or photocopier found at the scene, or determine compatibility or incompatibility with a machine found in a suspect s possession 7

8 VI. Proper Packaging of Evidence A. Consideration in handling evidence 1. Preserve its value for the owner 2. Mark the evidence for identification in court B. Collect and store it in a way that preserves its integrity for forensic comparison and analysis 1. Handle it in a manner which is not consistent with the normal handling of that type of item (i.e. do not grab a firearm by the grip) 2. Package the item to preserve it for processing and presentation 3. The purpose of proper packaging of physical evidence is to prevent breaking, spoilage, loss, destruction, and contamination between pieces of evidence C. Package each item of evidence separately D. Standard Packaging Requirements 1. All property except narcotics and dangerous drugs shall be packaged in an appropriately sized container or plastic bag 2. Knives should be placed in sharps tubes if they do not fold closed; the tube should be sealed with red evidence tape and initialed by the securing officer 3. A knife that folds closed should be secured with tape so that the blade does not open, and then it should be placed in plastic 4. Once property is sealed in a plastic bag, cover all sealed ends with red evidence tape 5. After the evidence tape is properly applied, date and initial both sides of the tape on each piece E. A packaging container or red evidence tag contains the following information 1. Case number 2. Offense 3. Location of the offense 4. Date of the offense 5. Description of the evidence including any model or serial numbers F. Place properly packaged evidence and transmittal in evidence lockers for safe storage G. Biological Fluids Requirements 1. Wet evidence must be air dried prior to packaging; this is to prevent rot and mildew of the evidence 2. Evidence with bodily fluids needs to be packaged in paper after it has dried 3. Liquid, sexual assault kits, or whole blood must be refrigerated as soon as possible 8

9 H. Firearms Requirements 1. When dealing with firearms as evidence, the following information must be noted and/or sketched: a) The physical appearance of the weapon before it is moved b) The position of the bolt, slide, or chamber c) The position of the hammer and/or safety d) The position of the cylinder and the position of the fired or unfired cartridges within the cylinder 2. Securing the weapon may not mean unloading the weapon; you may have to use a zip tie to keep the gun from moving from its collected state 3. Never put any objects into the barrel of the weapon 4. Package it in plastic 5. Package the ammunition separately I. Narcotics and Dangerous Drugs Requirements 1. Package all narcotics and dangerous drugs separately 2. Package drug paraphernalia separately 3. Weigh each type of drug in its entirety, including the packaging 4. Conduct a presumptive test on the substance, and include the results in the officer s report 5. Package narcotics and other drugs in paper envelopes 6. Seal both ends of the envelope with evidence tape 7. Initial and date the evidence tape on both ends 8. After narcotics/drugs are packaged a) Weigh them again in the completed packaging b) Write the gross weight on the outside of the package 9. Place a completed property tag on the package J. Cash 1. Count it in the presence of a supervisor 2. Initial it (the booking officer and the supervisor) 3. For cash in excess of $1,000, the sergeant shall be contacted and witness the count and initial, date the property form, and specify any additional security procedures to be used VII. Chain of Custody A. Must maintain a document that includes exactly what happened to the evidence from the time it was found to the time it is presented in court B. Accounts for the following information 1. Who found the item 2. Where it was found 3. Who took custody, collected, marked, and packaged the item 4. Where the item is stored C. Bears the name, initials, or mark of every person who came into 9

10 contact with all items of evidence D. Evidence Transmittal Sheet 1. Documents the chain of custody for the listed items of evidence 2. Includes a list of all items of evidence that is numbered consecutively 3. Continues the consecutive number onto more than one sheet if needed VIII. Protecting the Crime Scene A. The first officer to arrive at the scene of a crime must 1. Preserve and protect the area 2. Establish a perimeter to encase the crime scene B. Additional personnel will be needed for proper perimeter security C. After a perimeter is established, no one will enter the scene except 1. Crime scene personnel 2. Investigator in charge 3. Medical Examiner 4. Medical personnel, if needed 5. Those authorized by the crime scene unit or the personnel in charge D. Station officers at the entry and exit of the crime scene who will 1. Be responsible for keeping a Crime Scene Entry Log 2. Record everyone that enters or exits the crime scene IX. Lift and Preserve Developed Latent Prints (from a mock crime scene) A. Processing Prints 1. Put on protective clothing and gloves 2. Handle the piece of evidence by the edges or otherwise as needed to avoid damaging the latent prints 3. Place the object on a clean, flat surface with the suspected location of the latent print accessible 4. Dip the brush lightly into the powder (just the tips) 5. Tap the brush on the powder container to remove any excess powder 6. Use a light, circular motion to gently sweep the brush over the area to be processed while allowing the bristles to barely contact the surface 7. Continue to brush powder over the designated area until the latent prints begin to develop 8. Concentrate on that area as the location of the latent print becomes clear 9. Repeat steps 4 6 if necessary 10. Stop dusting once the print is clearly developed 11. Take a photo of the processed print B. Lifting Prints 10

11 1. Put on protective clothing and gloves 2. Find the free end on a roll of tape 3. Fold the end of the tape several times to make a tab to hold (this does not have to be neat) 4. Pull out 2 3 inches of tape 5. Avoid contact with the sticky side of the tape while holding the roll in one hand and the tab in the other 6. Choose the print you want to lift 7. Starting with the tab end, place the tape a few inches from the print and slide your finger across the tape to smooth it over the print while making sure all of the bubbles are gone 8. Peel the tape gently from the surface being processed 9. Begin at the end closest to the roll, place the latent print card against the roll of tape, and gently smooth the tape onto the card until the tab is reached 10. Tear the tape off carefully at the end of the latent print card and repeat steps 2 8 as needed X. DNA A. DNA Defined 1. DNA is the fundamental building block for an individual s entire genetic makeup; it is a component of virtually every cell in the human body 2. DNA is different for each person, except identical twins; this difference will either link or eliminate a suspect based on comparison 3. Common types of DNA a) Blood b) Saliva c) Skin cells d) Semen or vaginal secretions e) Hair B. DNA Collection 1. Wear gloves and change them often 2. Use disposable instruments or clean the instruments thoroughly before and after handling each sample 3. Avoid touching the area where you believe the DNA may exist 4. Avoid talking, sneezing, and/or coughing over the evidence 5. Avoid touching your face, nose, and/or mouth when collecting and packaging evidence 6. Air dry evidence thoroughly before packaging 7. If the sample is dry, moisten the swab with sterile, distilled water 8. Put the evidence into new paper bags or envelopes; do not package it in plastic 9. Do not use staples 11

12 C. Contamination can easily occur when one source of DNA gets mixed with another D. Transport and Storage 1. Keep the sample dry and at room temperature 2. Secure the evidence in paper bags or envelopes 3. Seal and label the envelopes 4. Transport in a manner that the location found and the proper chain of custody are visible 5. Avoid direct sunlight and warm conditions Activities 1. Mock Crime Scene. Before class, create a mock crime scene and organize the CSI materials (listed below). Divide the students into groups of six. Assign each student a role. Each team has a first responding officer, a recorder, a photographer, a sketch artist, and two designated evidence collectors. Distribute the CSI materials (see the list in the materials section) and the Evidence Collector s Checklist, First Responder Checklist, Photographer s Checklist, Recorder s Checklist, and Sketch Artist Checklist. The first officer on scene will secure the crime scene. The photographer and the sketch artists will document the crime scene. Then the evidence collectors will collect the evidence for later processing. Each team will turn in Completed Crime Scene Entry Log Evidence Transmittal Log Two sketches with accurate measurements (one rough and one quality) A series of photographs that adequately encompass the crime scene, including close up shots of evidence, numbered and photographed next to a ruler Evidence bags properly packaged, labeled, and sealed Completed checklists (Evidence Collector s Checklist, First Responder Checklist, Photographer s Checklist, Recorder s Checklist, and Sketch Artist Checklist) A one page summative report Use the Mock Crime Scene Activity Rubric and the Group Evaluation Rubric for assessment. 2. Search Method Activity. Preparation: Select a grassy area that is large enough to conduct a search (determine the appropriate size of the needed area according to the number of students in each class). Obtain spent (used) shell casings (gun ammunition) from a local resource (i.e. police department training academy or gun shooting range). Twenty shell casings per class should be sufficient. Realize that the students will probably not locate all of the ammunition during their search, so be sure to have enough casings to replace any lost during each class. Prior to class, spread the shell casings over the entire designated area and 12