Unit 4: Selection and Crime Scene Process
Basic Stages in a Crime Scene Search
1) Approach scene
2) Secure and protect scene
3) Initiate preliminary survey
4) Evaluate physical evidence possibilities
5) Prepare narrative description
6) Depict scene photographically
7) Prepare diagram/sketch of scene
8) Conduct detailed searchlRecord and collect physical evidence
9) Conduct final survey
10) Release crime scene
1. Approach Scene
a. Be alert for discarded evidence.
b. Make pertinent notes.
c. Establish frame-of-mind to take control of scene regardless of circumstances observed on arrival.
d. Consider personal safety.
2. Secure and Protect Scene
a. Take control aggressively on arrival.
b. Determine extent to which scene has thus far been protected.
c. Check for adequate scene security even if advised that it has been protected prior to arrival.
d. Obtain information from logical personnel who have entered scene and have knowledge relative to its original conditions.
e. Identify one individual who is designated as the person-in-charge for final decision making and problem resolution.
f.Take extensive notes - do not rely on memory.
g.Keep out unauthorized personnel - begin recording who enters and leaves.
3. Initiate Preliminary Survey
a. The survey is an organizational stage to plan for the entire search.
b. A cautious walk-through of the scene is accomplished.
c. Person - in - charge maintains definite administrative and emotional control.
d. Select appropriate narrative description technique.
e. Acquire preliminary photographs.
f. Delineate extent of the search area - usually expand initial perimeter.
g. Organize methods and procedures needed - recognize special problem areas.
h. Determine manpower and equipment needs - make specific assignment
1. Identify and protect transient physical evidence.
J. Develop a general theory of the crime.
k. Make extensive notes to document scene physical and environmental conditions, assignments
4. Evaluate Physical Evidence Possibilities
a. This evaluation begins upon arrival at scene and becomes detailed in preliminary survey stage.
b. Based on preliminary survey, establish evidence types most likely to be encountered.
c. Insure collection and packaging equipment is sufficient for task at hand - a given scene may require special techniques not normally used.
d. Concentrate on the most-transient evidence and work to the least transient forms of this material.
e . Insure all personnel consider the great variety of possible evidence, not only evidence within the scope of their respective specialties.
f. Focus first on the easily accessible areas in open view and progress eventually to possible out-of- view locations - look for purposely hidden items.
g. Consider whether the evidence appears to have been moved inadvertently.
h. Evaluate whether or not the scene and evidence appears intentionally “contrived”.
5. Prepare Narrative Description
a. The narrative is a running, general terms description of the condition of the crime scene.
b. Represent scene in a “general to specific” reference scheme.
c. Photographs supplement narrative description at this point.
d. Use systematic approach in recording narrative - no item is too insignificant to record if it catches one’s attention.
e. Do not permit narrative effort to degenerate into a sporadic and unorganized attempt to recover physical evidence - it is recommended that evidence not be collected at this point, under most circumstances.
f. Methods of narrative - written, audio, video (sight / sound or sight only).
6. Depict Scene Photographically
a. Begin photography as soon as possible - plan before photographing.
b. Document the photographic effort with a photographic log.
c. Insure that a progression of overall, medium and close-up views of the scene is established.
d. Use recognized scale device for size determination when applicable.
e. When a scale device is used first take a photograph without the inclusion of this device.
f. Photograph evidence in place before its collection and packaging.
g. Be observant of and photograph areas adjacent to the crime scene - points of entry, exits, windows, attics, etc.
h. Consider feasibility of aerial photography.
i. Photograph items, places, etc., to corroborate the statements of witnesses, victims, suspects.
j. Take photographs from eye-level, when feasible, to represent scene as would be observed by normal view.
k. Photographs are two-dimensional and are usually supplemented by diagrams and sketches.
l. Film is relatively cheap compared to the benefits obtained. Do not hesitate to photograph something which has no apparent significance at the time but may later prove to be a key element in the investigation.
7. Prepare diagram / sketch of scene
a. The diagram establishes permanent record of items, conditions and distance/size relationships. Diagrams supplement photographs.
b. A rough sketch is drawn at the scene, usually not to scale.
c. Typical items included in the sketch:
1) specific location
2) date
3) time
4) case identifier
5) preparer/assistant
6) weather conditions
7) lighting conditions
8) scale or scale disclaimer
9) compass orientation
10) evidence
11) measurements
12) key or legend
d. Number designations on sketch can be coordinated with same number designations on evidence log in many instances.
e. This sketch should contain sufficient measurements and detail to be used as a model for a drawn-to- scale diagram, if necessary.
f. Be sure to select sketch technique before beginning sketch. Insure that enough room is allowed to include all pertinent information and measurements.
g. General progression of sketches:
1) layout basic perimeter
2) set forth fixed objects, furniture, etc.
3) insert evidence as it is recovered.
4) record appropriate measurements.
5) set forth key/legend, compass orientation, etc.
8. Conduct Detailed Search Record and Collect Physical Evidence
a. Accomplish search based on previous evaluation of evidence possibilities.
b. Conduct search in a general manner and work to the specifics regarding evidence items.
c. Use of specialized search patterns (e.g.: grid, strip/lane, spiral) is recommended when possible.
d. Photograph all items before collection and enter notations in photographic log. Use a scale when necessary.
e. Mark evidence locations on diagram/sketch.
f. Complete evidence log with appropriate notations for each item of evidence.
g. Have at least two persons:
1) see evidence in place before collection.
2) observe it being recovered.
3) mark evidence (mark item itself whenever feasible).
4) place identifying marks on evidence containers.
h. If feasible, have one person as an evidence custodian - especially in relatively complicated crime scenes involving large amounts of evidence.
i. Do not excessively handle evidence after recovery.
j. Seal all evidence containers at the crime scene.
k. Do not guess on packaging requirements - different types of evidence can require different containers.
l. Do not forget entrance and exit areas at scene for potential evidence.
m. Be sure to obtain appropriate “known” standards (e.g.: fiber sample from carpet).
n. Do not rely on devices and chemical tests without a full evaluation of all factors, Vacuuming for evidence, for example.
o. Constantly check paperwork, packaging notations and other pertinent recordings of information for possible errors which may cause confusion or problems at a later time.
p. Four basic premises to consider
1) The best search options are typically the most difficult and time-consuming.
2) You cannot over-document the physical evidence.
3) There is only one chance to perform the job properly.
4) There are two basic search approaches, in this order:
a) a “cautious” search of visible areas, taking steps to avoid evidence loss or contamination.
b) after the “cautious” search, a vigorous search for hidden! concealed areas.
9. Conduct Final Survey
a.This survey is a critical review of all aspects of the search.
b.Discuss search jointly with all personnel for completeness.
c.Double-check documentation to detect inadvertent errors.
d.Insure that photographs are taken of scene showing final condition after completion of search.
e.Check to insure all evidence is accounted for before departing scene.
f.Insure all equipment used in the search is gathered.
g.Make sure possible hiding places or difficult access areas have not been overlooked in detailed search.
h.Critical issues: have you gone far enough in the search for evidence, documented all essential things and made no assumptions which may prove to be incorrect in the future?
10.Release Crime Scene
a. Release is accomplished only after completion of the final survey.
b. At minimum, documentation should be made of:
1) time and date of release
2) to whom released
3) by whom released
c. Insure that appropriate inventory has been provided, as necessary considering legal requirements, to person to whom scene was released.
d. Once the scene has been formally released, re-entry may require a warrant.
e. Only the person-in-charge should have the authority to release the scene. This precept should be known, and adhered to, by all personnel.
f. Release the scene with the notion that there is only one chance to perform the job correctly and completely. Release then occurs once personnel are satisfied this is the situation.
g. Consider the need to have certain experts observe the scene before it is released.