A crime scene search is a planned, coordinated, and legal search by law enforcement officials to locate physical evidence.
Basic Premises
- The best search options are typically the most difficult and time-consuming.
- Physical evidence cannot be over-documented.
- There is only one chance to search the scene properly.
- There are two search approaches:
- Conduct a cautious search of visible areas, avoiding evidence loss or contamination
- After the cautious search, conduct a vigorous search of concealed areas
Preparation
- Obtain a search warrant, if necessary.
- Discuss the search with involved personnel before arrival at the scene, if possible.
- Establish a command headquarters for communication and decision making in major or complicated crime scene searches.
- Ensure that personnel are aware of the types of evidence usually encountered and the proper handling of the evidence.
- Make preliminary personnel assignments before arrival at the scene, if possible.
- Ensure that assignments are in keeping with the attitude, aptitude, training, and experience of personnel. Personnel may be assigned two or more responsibilities.
- Person In Charge
- Scene security
- Administrative log
- Preliminary survey
- Narrative description
- Problem resolution
- Final decision making
- Photographer
- Photography and log
- Sketch Preparer
- Sketch and log
- Evidence Recorder
- Evidence custodian and log
- Establish communication between medical examiners, laboratory personnel, and prosecutive attorneys so that questions during the crime scene search can be resolved.
- Coordinate agreements with all agencies in multijurisdictional crime scene searches.
- Accumulate evidence collection and packaging materials and equipment.
- Prepare the paperwork to document the search.
- Provide protective clothing, communication, lighting, shelter, transportation, equipment, food, water, medical assistance, and security for personnel.
- In prolonged searches, use shifts of two or more teams.
- Transfer paperwork and responsibility in a preplanned manner from one team to the next.
Approach
- Be alert for evidence.
- Take extensive notes.
- Consider the safety of all personnel.
Secure and Protect
- Take control of the scene immediately.
- Determine the extent to which the scene has been protected. Obtain information from personnel who have knowledge of the original condition.
- Designate one person in charge for final decision making and problem resolution.
- Continue to take extensive notes.
- Keep out unauthorized personnel.
- Record who enters and leaves.
Preliminary Survey
- The survey is an organizational stage to plan for the search.
- Cautiously walk through the scene.
- Maintain administrative and emotional control.
- Select a narrative technique such as written, audio, or video.
- Take preliminary photographs.
- Delineate the extent of the search area. Usually expand the initial perimeter.
- Organize methods and procedures.
- Recognize special problem areas.
- Identify and protect transient physical evidence.
- Determine personnel and equipment needs. Make specific assignments.
- Develop a general theory of the crime.
- Take extensive notes to document the scene, physical and environmental conditions, and personnel movements.
Evaluate Physical Evidence Possibilities
- This evaluation begins upon arrival at the scene and becomes detailed in the preliminary survey stage.
- Ensure that the collection and packaging materials and equipment are sufficient.
- Focus first on evidence that could be lost. Leave the least transient evidence last.
- Ensure all personnel consider the variety of possible evidence, not only evidence within their specialties.
- Search the easily accessible areas and progress to out-of-view locations. Look for hidden items.
- Evaluate whether evidence appears to have been moved inadvertently.
- Evaluate if the scene appears contrived.
Narrative
- The narrative is a running description of the crime scene.
- Use a systematic approach in the narrative.
- Nothing is insignificant to record if it catches one's attention.
- Under most circumstances, do not collect evidence during the narrative.
- Use photographs and sketches to supplement, not substitute for, the narrative.
- The narrative should include
- Case identifier
- Date, time, and location
- Weather and lighting conditions
- Identity and assignments of personnel
- Condition and position of evidence
Photography
- Photograph the crime scene as soon as possible.
- Prepare a photographic log that records all photographs and a description and location of evidence.
- Establish a progression of overall, medium, and close-up views of the crime scene.
- Photograph from eye level to represent the normal view.
- Photograph the most fragile areas of the crime scene first.
- Photograph all stages of the crime scene investigation, including discoveries.
- Photograph the condition of evidence before recovery.
- Photograph the evidence in detail and include a scale, the photographer's initials, and the date.
- When a scale is used, first take a photograph without the scale.
- Photograph the interior crime scene in an overall and overlapping series using a wide-angle lens.
- Photograph the exterior crime scene, establishing the location of the scene by a series of overall photographs including a landmark. Photographs should have 360 of coverage. Consider using aerial photography.
- Photograph entrances and exits.
- Photograph important evidence twice.
- A medium-distance photograph that shows the evidence and its position to other evidence.
- A close-up photograph that includes a scale and fills the frame.
- Acquire prior photographs, blueprints, or maps of the scene.
Sketch
- The sketch establishes a permanent record of items, conditions, and distance and size relationships.
- Sketches supplement photographs.
- Sketch number designations should coordinate with the evidence log number designations.
- Sketches are normally not drawn to scale. However, the sketch should have measurements and details for a drawn-to-scale diagram, if necessary.
- The sketch should include
- Case identifier;
- Date, time, and location;
- Weather and lighting conditions;
- Identity and assignments of personnel;
- Dimensions of rooms, furniture, doors, and windows;
- Distances between objects, persons, bodies, entrances, and exits;
- Measurements showing the location of evidence. Each object should be located by two measurements from non-movable items such as doors or walls; and
- Key, legend, compass orientation, scale, scale disclaimer, or a combination of these features.
Crime Scene Search, Record, and Physical Evidence Collection
- Use a search pattern such as a grid, strip or lane, or spiral.
- Search from the general to the specific for evidence.
- Be alert for all evidence.
- Search entrances and exits.
- Photograph all items before collection and notate the photographic log.
- Mark evidence locations on the sketch.
- Complete the evidence log with notations for each item of evidence. If feasible, have one person serve as evidence custodian.
- Two persons should observe evidence in place, during recovery, and being marked for identification. If feasible, mark directly on the evidence.
- Wear gloves to avoid leaving fingerprints.
- Do not excessively handle the evidence after recovery.
- Seal all evidence packages at the crime scene.
- Obtain known standards such as fiber samples from a known carpet.
- Make a complete evaluation of the crime scene.
- Constantly check paperwork, packaging, and other information for errors.
Final Survey
- The final survey is a review of all aspects of the search.
- Discuss the search with all personnel.
- Ensure all documentation is correct and complete.
- Photograph the scene showing the final condition.
- Ensure all evidence is secured.
- Ensure all equipment is retrieved.
- Ensure hiding places or difficult access areas have not been overlooked.
Release
- Release the crime scene after the final survey.
- Crime scene release documentation should include the time and date of release, to whom released, and by whom released.
- Ensure that the evidence is collected according to legal requirements, documented, and marked for identification.
- Consider the need for specialists such as a blood-pattern analyst or a medical examiner to observe the scene before it is released.
- Once the scene has been released, reentry may require a warrant.
- The scene should be released only when all personnel are satisfied that the scene was searched correctly and completely.
- Only the person in charge should release the scene.