Docstoc

1 Crime Scene Procedures

Document Sample
1 Crime Scene Procedures Powered By Docstoc
					                          Crime Scene Procedures
                                                 by
                                     Jeffrey C. Kercheval, MFS
                                      Hagerstown Police Dept.

Initial Response
A. Search of area/premises for suspects (self protection)
        If you are the first officer arriving at a crime scene, your safety is a primary concern.
        Make certain there are no eminent threats or hazards which may cause you harm.

B. Provide medical assistance if applicable
        If injured persons are found at the scene, rendering first aid is a matter of priority. (If
        sufficient police personnel are present/available...first aid may be performed in
        conjunction with sealing off scene.)

C. Protection of the scene
        1     Protection includes sealing off any critical area likely to yield evidence. Take
              precautions depending on weather (rain, snow, smog, etc.), and areas of access and
              egress.
        2     Considerations include:
               destruction of evidence
               contamination of evidence
               providing and maintaining chain of custody for evidence
               have a recorder...records everyone who enters scene along with time also make
                  note of weather.
        3     Protection---underlying intent---
               prevent unnecessary walking about
               moving items
               touching surfaces
               removing items from the scene

D. Other initial actions...
        1     arresting suspects
        2     detaining witnesses


General Guidelines
A.   The individuals responsible for processing and investigating the crime
     scene should get all available information from those already present before entering the
     scene.


Crime Scene Procedures                                                                           page 1
B.   Preliminary examination (observation-no collection). Prior to beginning
     any search, a walk-through evaluation of the crime scene should be performed. The walk-
     through should be performed by those individuals responsible for processing the scene.
     During the walk-through evaluation, investigators are observing only. This evaluation
     process is one of the most critical phases of processing any crime scene for evidence. The
     impressions gained from this walk-through are going to formulate how the scene is
     processed. During the walk-through, it is a good practice to place your hands in your pockets
     to make certain that you do not touch anything. Move through the scene by walking in areas
     which do not appear to contain any potential evidence. Extra care must be exercised when
     walking through hallways, doorways or in entry foyers to protect any potential
     footprint/footwear impressions, fingerprints, trace evidence, etc. Some of the basic
     information gained from a walk through includes:
         1 Any sign of a forced entry into an indoor crime scene
         2 Locations of access into and egress out of the crime scene
         3 Location of potential items of evidence
         4 Presence/absence of blood in various areas of the scene
         5 Evaluating the scene geometry (spatial relationship of various objects, including
             victims, within the scene)
         6 Evaluating any deceased victims which may be present to include:
             a Observing presence/absence of trauma
             b Evaluating body condition for approximate time since death
             c Observing any objects present on/in the victim which may be associated with the
                 crime

The initial officer responding to the scene should accompany investigators on the walk through
evaluation to indicate if anything within the scene has been disturbed between the time of his/her
initial entry into the scene and when the processing phase has begun. It should also be noted that
an investigators impressions of a crime scene will usually undergo a metamorphosis from the
initial walk-through evaluation through scene processing, and later, as more information is
gained.

C.   Photograph the scene using both color and "black and white" film.
     Film is inexpensive so take numerous photos from various angles, distances, and at various
     camera settings. Consider videography of scene. Photography should be performed prior to
     disturbing the scene in any way.

        1 CRITICAL PHOTOGRAPHIC REQUIREMENTS
          a Consider perspective
          b General scenario shot
          c Photograph important individual items a) Overall photos showing the item
             photographed in its relation to the scene as a whole b) Intermediate photos
             showing the item in relation to its immediate surroundings c) Close-up detail
             photographs of items
          d Photographs of items and the overall scene areas from different angles
          e Approaches to the scene
Crime Scene Procedures                                                                   page 2
            f   Surrounding areas
            g   Close-ups of entrance & exit to the scene
            h   Photos of all good prints before lifting
            i   Blood stains...and anything else of importance or potential importance
            j   Use an identifying scale/rule when applicable

        2   PHOTOGRAPHY OF DECEASED OR INJURED PERSONS
            a Close-ups of all visible wounds, bruises, cuts, etc.
            b Close-up photos of hands and fingernails
            c Close-up photos of bindings, etc. if any are present on victim's body
            d Photographs of all wounds, bruises, etc., at scene and morgue
            e Use an identifying scale/rule when applicable

D.   Record the scene with a sketch. Photographs are only two dimensional. A rough
     crime scene sketch should be prepared at the crime scene following photography. This sketch
     does not need to be a work of art, but should contain enough information to allow a final or
     "finished" sketch to be prepared. A scene sketch will provide accurate spatial relationships of
     items within a scene. Currently there are numerous computer crime scene sketch programs
     available. These programs can be used to neatly and accurately create a final sketch from the
     rough sketch made a crime scene. Some of these programs (Sirchie Fingerprint Labs) provide
     crime scene template libraries which include a variety of computer clip-art images, such as
     victims in various positions, weapons, furnishings, etc. Any crime scene sketch should
     provide the
         1 Case number
         2 Description
         3 Date
         4 Measurements/scale
         5 Persons preparing the sketch
         6 Compass (north) indicator

        7   SKETCHING METHODS:
            a Coordinate method - measure the distance of an object from 2 fixed points.
              Measurements of an object are taken at right angles
            b Triangulation method - useful outdoors (too complicated indoors unless there are
              few pieces of evidence)
            c Cross Projection Method - useful when items or locations of interest are on walls,
              etc.

THE CRIME SCENE SKETCH MUST BE AN ACCURATE DEPICTION OF THE SCENE
TO BE ADMITTED INTO EVIDENCE...HOWEVER ALL ASPECTS OF THE DRAWING
DO NOT NEED TO BE TO EXACT SCALE!

E.   Areas of access and egress and evidence that are being deteriorated
     by time or the elements have first priority. If it is not feasible to initially
Crime Scene Procedures                                                                       page 3
     process areas of access and egress, the areas should be blocked off so no accidental entry can
     be gained by authorized crime scene personnel. My personal preference in homicide cases is
     to block off areas of access and egress and begin processing the body and the area around the
     body.

F.   If a deceased person(s) is involved, the body & area around the body
     and toward the exit area are processed first. Touching, moving and processing
     of the body should be performed following the arrival of the medical examiner/coroner. The
     body may be removed following photography & processing. Place protective paper bags (not
     plastic) over the victims hands prior to moving. This protects any evidence which might be
     present on the victims hands and/or under the fingernails.

G.   Processing of a deceased victim should include an on-scene "non-
     intrusive" evaluation of wounds/trauma, post mortem interval (time
     since death), and indicators which suggest that the body may have
     been moved. Basic indicators which are important for determining post mortem interval
     include:
         1 Rigor mortis
         2 Livor mortis
         3 Algor mortis
         4 Changes of the eye - corneal cloudiness, vitreous potassium
         5 Stage of body decomposition
         6 Forensic entomology
         7 Flora considerations at an outdoor scene
         8 Scene markers - mail, newspapers, etc.
         9 Basic indicators which may be used to suggest that the body may have been moved
            include:
            a Position of victim displaying rigor mortis
            b Location of livor mortis with regard to body position
            c Obvious indicators suggesting post mortem movement of body

H.   Major evidence items are collected. Remember...these may contain trace
     evidence and/or prints.

I.   Search for less obvious evidence & trace evidence.

J.   Adhesive lifts and vacuuming sweepings of areas of particular
     interest, if applicable. Care should be used when collecting vacuum sweepings. The
     vacuumed areas should be specific, not a general "house cleaning" of the crime scene. A
     large container of dust/hair/fibers and other trace evidence is extremely difficult and time
     consuming for laboratory personnel to examine.


Crime Scene Procedures                                                                        page 4
K.   Collection of exemplars:
        1   For comparison purposes from the scene
        2   From persons performing the scene processing..(for prints, etc.)
        3   From victim(s)
            a Blood
            b Hair
            c Nail clippings
            d Swabs from mouth, anus and vagina (if applicable)
            e Clothing
            f Scaled photographs of inflicted trauma and patterned injuries
        4   From suspect(s)
            a Blood
            b Hair
            c Clothing
            d Scaled photographs of any evident injuries

L.   Processing for prints. Processing for latent prints may contaminate areas of the crime
     scene with latent fingerprint powders, chemicals, etc. Therefore, it is prudent to perform
     latent print processing following documentation and collection of evidence. L) Complete as
     much information as possible on attached sheets scene with latent fingerprint powders,
     chemicals, etc. Therefore, this procedure is performed following documentation and
     collection of evidence.


M.      THE DON’Ts AT THE CRIME SCENE
        1  Unnecessary walking about
        2  Moving or disturbing the bodies of victims
        3  Touching items or surfaces likely to yield prints
        4  Allowing items to be removed from the crime scene without permission from the
           chief investigator
        5 Smoking
        6 Using toilet facilities
        7 Washing or using towels at scene
        8 Using telephone (unless already processed)
        9 Allowing entry of unauthorized personnel
        10 Commenting to news media or public




Crime Scene Procedures                                                                    page 5

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:17
posted:9/12/2011
language:English
pages:5