week 2

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Collection Phase - Measuring Evidence Location

Obtain Measurements of Evidence; Place on Sketch

Pre-Response Preparation

-check equipment -check vehicles -check weather forecast

Creating a Projection Sketch

1. Determine the view to be shown in the sketch: overhead or exploded. − The overhead view shows a floor plan. This is the most frequently used view in sketches. − The exploded view shows a floor plan with walls laid out flat. Objects on the floor and on walls, such as bullet holes or bloodstains, are shown in their relative positions in the exploded view sketch. 2. Draw an outline that is to scale of the area of interest, including locations of approaches and accurate measurements of the perimeter. The size of the outline should fill as much of the paper as possible. 3. Draw the rough sketch before anything is moved or destroyed, and after photographs are taken. Do not alter the scene. Show locations of windows and doors. Use a curved line to indicate the direction that each door opens. 4. Use only the selected units of measurement. The sketch or accompanying notes should indicate where a measurement of an object was taken (e.g., middle of the object, nearcorner, far-corner, etc.). Measurements of bloodstains are often done on a metric scale (e.g., millimeters). 5. Whenever possible, have another officer or crime scene investigator observe measurements for confirmation purposes. 6. Take accurate measurements of the exact locations and relative positions of evidence using the triangulation method when there are at least two fixed points within the outlined area. 7. Use triangulation indoors or outdoors; it is an especially good method to use in areas lacking straight lines. 8. Take measurements from fixed locations, such as a wall or curb, or from a stationary appliance. Identify these locations in your legend. 9. Measurements should be accurate to within ¼ inch. 10. Include height measurements to show how far off of the ground an object was found. 11. When determining distance based on triangulation: a) Select two fixed points within the outlined area, such as walls, curbs, or street signs. b) Draw a baseline between the two fixed points. c) Select another object within the outlined area. d) Measure the distance to that object from each of the baseline's fixed end points, creating a triangle. 12. Use a measuring tool to ensure accurate measurements are taken. 13. Take accurate measurements of the exact location and relative position of evidence using rectangular coordinates and the baseline method when: there are two known points or accurate measurements are needed for an object located on or perpendicular to the line between those two points (the baseline). 14. Use the baseline method in outdoor areas that are irregularly shaped and where no natural baseline is present. This method is useful in situations such as scenes that occur in the desert or on farmland. 15. Take measurements from fixed locations, such as a lamp post or curb, or from a stationary appliance. 16. Measurements should be accurate to within ¼ inch. 17. Include height measurements to show how far off of the ground an object was found. 18. When determining distance based on the transecting baseline coordinate method: a) Select two fixed points within (at the outer edges of) the outlined area, such as a kitchen appliance, a door, a window, a corner or wall (a wall is preferred). b) Create the baseline by drawing a line between the two selected fixed points. c) Measure the length of the baseline. d) Select an object within the outlined area. e) When the object is on the baseline, measure from one of the fixed end-points to the object. f) When the object is not on the baseline, draw a straight line from the object at a 90-degree angle to the baseline. g) Measure the length of the line drawn. h) Measure from one of the fixed end-points to the point where the new line meets the baseline 19. When a sketch is complete, prominently write "Not to Scale" outside of the sketch, then update related documentation, such as the legend and notes. Note: Although accurate measurements were taken, potential courtroom controversies related to those measurements may be avoided by placing the "Not to Scale" disclaimer on the rough sketch. 20. Ensure that all identification symbols used on the sketch are included and defined on the legend. 21. Include descriptive details related to the sketch in notes such as lighting conditions, names of people in the area, colors of objects, odors, weather. 22. Include updates such as distances between objects and dimensions of rooms, windows, doors, etc. 23. Until all rough sketches for a crime scene are complete, repeat the previous steps. 24. Do not update any rough sketch after leaving the scene. 25. Finish note-taking at the scene. Include the time that sketching was completed in the notes. Note-taking should occur throughout the sketching activities. 26. Finished sketches can be completed either by the originator of the rough sketches or by another staff member, such as a draftsperson or artist.

processing the scene

1. determine team composition 2.ensure contamination control 3.documentation

Videography

Equipment Needed • Video camera • Video kit with battery and recording media • Personal protective equipment • Additional sources of lighting • Camera cleaning supplies • Tripod • Pen • Notebook General Considerations Plan the video shoot carefully. Take video of the scene in its original state from multiple angles and distances. Take video of fragile evidence first. Avoid disturbing the scene. Always take video of the scene before and after alteration, such as when placards and scales are placed near evidence. Exclude officers, bystanders, and others at a scene from the video. Turn audio off. Take overall (long-range) video to show where the crime occurred, midrange video to show relationships of evidence and other points of interest, and close-up video to show individual items and their characteristics. Use a sturdy tripod whenever possible to reduce movement while taking video. Take video from angles that result in the best representation of that scene. Avoid panning side to side or up and down. Avoid zooming while out of focus. Always use the designated safe route when moving through the scene. When applicable, include the names of those assigned to specific tasks in your notebook. Plan the videography route. Take video of transient objects, such as bloodstains or latent prints, as soon as possible. Move from the exterior to the interior of the crime scene, and from general to specific focus. The videography session should occur in an uninterrupted, systematic, focused manner. When planning the route, ask: • How did the victim or suspect arrive at or leave from the scene? • How was the crime committed? • Which items were handled? • Which items were moved? • Which items are broken or stained? • Have potentially flammable vapors been detected at the scene? Caution: Some equipment is flammable. When potentially flammable conditions exist, appropriate precautions must be taken. Go beyond boundary markers to take video only when necessary. Plan and prepare lighting for each scene and camera angle. a) Front lighting places the camera lens at a 90-degree angle to the recorded object. It is often the most appropriate type of lighting to use at crime scenes. b) Side lighting places the lighting source at a 45-degree angle to an object. It is used: o to show details such as tool marks, surface irregularities or textures o to show vehicle accident damage o when videotaping in closets or other small spaces o when videotaping polished surfaces Control the use of lighting by manually changing the focus settings and turning on/off flash settings. It is important to have a detachable flash or, if the flash is not detachable, another light source. Turn audio off. Record overall video of the house/building exterior, vehicles, other structures at the crime scene, including entrances and exits, and bystanders. Slowly pan in one directional sweep; never move the camera side to side or up and down. Overall video should include a 360-degree view of the entire scene including landmarks, entrances and exits, and identifying marks, such as a house number or license plate. Always use slow camera movements such as when panning and zooming. Use a tripod whenever possible, unless using it will disturb either the scene or other team members. When recording a long, narrow area, such as a side yard or train tracks, use a tripod and slow zooming. Always avoid walking while taping these shots Record entry/exit points from all possible angles. Show any paths used during the crime, when possible. While taking video of a scene, record related information in notes. Specify any changes made to a scene while taking video, such as when a light was turned on or the tripod left a mark. Film midrange and close-up exterior video (within 5 feet of subject) immediately following the overall recording of a scene. Record in a systematic, focused way.

Initial Phase - Formulate Evidence Collection Plan

Generally, the evidence collection plan is based on a logical progression through the scene, minimizing unnecessary movement where possible. However there are other factors that influence the collection plan: Is the evidence fragile, or could be easily lost? Are there environmental factors? Can the scenes, or parts thereof, be adequately protected?

Additional Techniques for Close-up Photography

If not using a digital camera, photograph wounds using color film. Carefully place the camera perpendicular relative to the wounds to obtain accurate measurements. Photograph the body of a deceased person before moving it and also photograph it at the morgue. Include scales where appropriate. • Adjust lighting when photographing the wounds to obtain the best contrast and result. Take multiple shots with the light held or placed at different angles to the subject in order to achieve the best results. • Retake photographs of wounds such as bruises at different intervals to capture changes, such as in color, over several days.

procedure for determining team composition

a. Assess the need for additional personnel. They should be aware of the need for additional personnel in cases involving multiple scenes, multiple victims, numerous witnesses or unique circumstances. b. Assess forensic needs and call forensic specialists to the scene for expertise and/or equipment. c. Ensure that scene security and the entry/exit documentation are continued. d. Select qualified person(s) to perform specialized tasks (e.g., photography, sketch, latent prints, evidence collection). e. Document team members and assignments.

Common crime scene investigation photography is an important part of the documentation of a crime scene. Photographs are typically taken based upon the perspective of the camera to the target.

a. Overall b. Midrange c. Close-up

The thorough search of a crime scene helps ensure that

all relevant evidence will be recognized, documented and collected

strip or line search

are accomplished by the searchers walking in parallel along defined lanes in the same direction.

Minimize contamination by

being safe, clean and careful to ensure the welfare of personnel and the integrity of the evidence

Conducting the Scene Investigation Initial Phase - Approach to Scene

camera flashlight notepad gloves

oblique lights used to

check surfaces before proceeding and they can "reveal" potential evidence

post scene activities

conduct critique conduct follow-up prepare for court court testimony critique / lessons learned incorporate lessons learned

collection phase: scene processing

formulate evidence collection plan document evidence preliminary examination of evidence collect evidence package evidence preserve evidence

A well-documented scene ensures the

integrity of the investigation and provides a permanent record for later evaluation.

grid method

is a lane search that is conducted by completing a lane search in one direction and then completing a lane search in a perpendicular direction. While it takes twice as long as a lane search, it provides a more thorough search of an area.

post scene activities

lab submission prep- evidence assessment submit evidence for lab analysis prepare written reports

categories of sketches

perspective projection schematic detailed

The assessment of the scene(s) determines

the number of personnel and how responsibilities will be assigned.

flashlights used

to help focus eyes on area being searched

There are four measuring techniques used to obtain accurate measurements for the sketch:

triangulation method rectangular coordinate method polar coordinate method transecting baseline coordinate method

The triangulation method

utilizes two fixed permanent objects within the crime scene. Measurements are taken from each fixed point to each piece of evidence.

Crime Scene search personnel should approach the investigation of a scene as if it

will be their only opportunity to preserve and recover clues

Secure the Scene & Protect Evidence:

• Limit unnecessary movement into and about the scene: • Post officers at the perimeter of the scene • Use banner guard or other physical barriers • Create a log of all persons who enter the scene • Be prepared to address fragile / transient evidence upon arrival /

Collection Phase - Evidence Photography

Take Mid-range and Close-up Photographs of Evidence

Final Phase - Associated Tasks

Latent Print Processing Overall measurements of entire scene; fix measurement reference points Other Key measurements - areas of high activity / high interest Supplemental Photography Scene Reconstruction considerations (bloodstain patterns, ballistics/trajectory

documentation general considerations

A sketch of a crime scene is required when spatial relationships or proportional measurements are needed. Use spatial relationships to relate evidence to other objects. Use proportional measurements to calculate such things as bullet trajectory angles or to reconstruct accident details. The rough sketch is the first sketch drawn at the scene; multiple rough sketches may be required depending on the crime. The sketch includes a scene outline with the location of objects and evidence clearly marked. A finished sketch is derived from the rough sketch. Draw the rough sketch before anything is moved or destroyed, and after photographs are taken. Do not alter the scene. Depending on the crime, draw one or all of these types of sketches: a sketch showing the surrounding areas, a sketch showing only measurements, and a sketch showing locations of objects, such as the locations of evidence, victim(s), etc. Measurements should be accurate to within ¼". Include, outside of the drawn crime scene, measurements for dimensions of rooms, furniture, doors and windows, and distances between objects, entrances and exits, bodies and persons. Draw details, such as object size, proportionally in a rough sketch. Take measurements from fixed location reference point, such as walls or curbs, or from stationary appliances. Include as much information as possible in the sketch: streets, plants, entry and exit points, location of bullets and cartridges, etc. Do not alter a rough sketch after leaving the crime scene. If changes are required of the rough sketch, photocopy the original rough sketch to preserve its integrity. Newer technology makes use of laser scanning devices to perform crime scene sketching. The employment of these devices should be reserved to investigators trained in their use.

Collection Phase - Addressing Physical Evidence

Address each item of evidence completely before moving on to the next items Each item of physical evidence should be given a unique identifier for the case under investigation (typically assigned a number) The same unique identifier will be used across all documentation The unique identifier should be given just before addressing the item ; do not 'pre-number' your physical evidence / Assign Unique Identifier

Collection Phase - Packaging Evidence

All evidence should be secured in suitable packaging material or containers • different types of evidence require different packaging techniques or containers All packaging material or containers must be clean/unused Choose appropriate packaging material Bring packaging material / container to item /

Collection Phase - Evidence Package Labeling

All packaging material / containers should be labeled prior to placement of evidence • hard to write on material after item has been placed inside\ • sharpie marker can "bleed through" material and onto the evidence\ • writing pressure can damage evidence (e.g. indented writing, fragile items) All containers should have the openings sealed and initialed by investigator Begins the process to track physical evidence - 'Chain of Custody'

Important Rules to Remember

Always follow a Systematic Approach If you alter your normal routine be sure to document why Environmental conditions will always dictate how you address the scene Better to take the extra step, rather than ignore /

Initial Phase - Formulate Evidence Collection Plan

Are there investigative lead priorities? Are there political pressures? Recognize other technical / scientific methods that are available to locate, document, and/or collect evidence (e.g., Alternate Light Source, Presumption Tests for Blood and Semen, Latent Print development)

Conducting the Scene Investigation Initial Phase - Scene & Evidence Security

Assess Scene Security (initial) Assess initial 'boundaries' set by others prior to your response. (Rule of thumb - double initial boundaries set by first responders) Assess need to deal with fragile / transient evidence to avoid loss or contamination /

Collection Phase - Preventing Contamination

Be aware of possible cross-contamination; clean/sanitize tools and equipment between items of evidence Consider use of disposable tools Change gloves between collection of separate biological samples, or items with potential biological evidence; or when collecting evidence from different areas of the scene Carefully examine evidence prior to placing in container /

Collection Phase - Collecting Other Evidence Samples

Collect Control Samples, as appropriate (e.g., substrate controls) Collect Standard / Reference Samples from the scene (e.g., carpet, soil, dust/debris, etc.) Collect Known Reference Samples from suspect(s): Collect Elimination Samples (victim / witnesses / others who frequented the scene) Collect supporting/secondary Evidence (supports theory of case or an element of the criminal act)

Preliminary Scene Survey Activities

Continue Note Taking - Record all observations; note type and location of potential evidence Take Overall Photographs during scene survey • Supplement with Video as deemed necessary Initiate Rough Sketch Formulate Evidence Collection Plan Establish Equipment / Collected Evidence Staging Area

Conducting the Scene Investigation Initial Phase - Questioning 1st responding officers present at the scene upon your arrival:

Do they know what happened? Has he/she been in the scene? If so, where did they walk. Has anyone else gone into scene? Has anyone touched or moved anything? Location of victim / witnesses present during incident? /

Final Phase - Final Walk-Through

Done initially by the Scene Investigator Done to ensure all potential evidence has been collected Done to ensure all equipment has been removed from scene Done to ensure all theories of the case have been thoroughly evaluated Conduct another Final Search with Fresh Eyes

Collection Phase - Examining Physical Evidence

Examine Physical Evidence • Each item of evidence should be documented, carefully examined, collected and placed in its container before moving to the next item of evidence • Record in Notes your observations concerning condition of evidence and any distinguishing markings • Take additional photographs as needed to further document evidence examination observations /

Initial Phase - Establish Safe Areas for Equipment

Find a safe and secure location within the scene to stage the equipment you'll need to investigate the scene. Fully document and search the area prior to placement of equipment.

Contributors to a Successful Crime Scene Investigation

First Responding Officers Case Investigator / Detective Crime Scene Investigators Forensic Scientists / Other Subject Matter Experts Medical Examiner

Conducting the Scene Investigation Initial Phase - Approach to Scene

Park safe distance from scene (initially); approach on foot Have 1st officer come to perimeter for briefing Assess potential Hazards / Threats Understand legal basis to approach scene and undertake investigative activities Assess need to intervene to protect fragile evidence Assess need for additional resources /

film photography

Plan the type of film to be used for a series of photographs when anticipating taking midrange then close-up photographs immediately after overall photographs. If it is anticipated that a change of film will be necessary, change the film before taking the overall photographs. Black-and-white film: Use black-and-white film for close-up photographs of fingerprint/footprint/shoeprint/tire track evidence. Color film: Use color film for close-up photographs of bloodstains and other bodily fluids. Take overall photographs of the area surrounding the scene from its perimeter, from multiple locations and angles. Include exteriors of buildings, cars, both sides of entries and exits, and bystanders. Overall photographs should: • Encompass the entire large scene and be overlapping • Represent a 360-degree perspective and include a landmark • Include identifying marks, such as house number(s) or license plate(s) Overall photos may also encompass smaller "sub-scenes" that exist within the larger scene. For indoor scenes, consider photography from each corner of a room, looking into the room. After the scene is photographed as found, additional photographs with placards, used as evidence identifiers, must be wholly visible in overall photographs when they are used, such as when midrange and close-ups will be taken of the scene. They must be placed in close proximity to the subject(s) of the photograph. While taking photographs of a scene, record related information in notes. It is critical to use a systematic approach to note-taking while taking photographs to maintain a record of your activities and the order and location of pictures as they are taken. Specify the changes you made to a scene while taking photographs, such as when a light was turned on or objects were moved. Note-taking should occur throughout the photography session. Finish note-taking at the scene. Include the time that photographing began and was completed in the notes. Midrange Photographs Take midrange photographs before and after placing placards or rulers. It is important to take photographs that establish the relationships of objects or reference points in the scene. Take close-up photographs immediately after taking the midrange photograph, when appropriate. It may be appropriate to follow midrange photographs of a scene with close-up pictures of the same scene when showing a scene before, during, and after placard/ruler placements, nearviews of human injuries or vehicle accident damage. While taking photographs of a scene, record related information in notes. Take photographs of transient evidence from a position that: • Shows the spatter relative to other objects in the area • Is perpendicular to the spatter Take pictures of the scene before and after placing the placards and rulers, and after removing the placards and rulers. Photographing the Deceased Before the body of a deceased person is moved, it should be photographed. The following guidelines should be followed: Take photographs from all possible angles. Show a facial view, and the positions of the hands and feet when possible to do so without altering the body, its clothing or position. Wound photography should be conducted at close-up range. Take photographs while moving around the body and from an overhead perspective. Photograph the body from two perspectives, when possible: a) As though looking at the body from a standing position b) From the same level as the body is lying, such as at ground level when the body is lying on the ground Use oblique lighting to show wounds on the body, such as bite marks, with and without a scale. After the deceased has been removed from the scene, photograph the area where the body was. Signs of activity can include: • TV and room lights turned on A glass holding a cold beverage (ice melting or still frozen) and a plate with fresh food on it • Scattered clothing, magazines, or other objects • A landline phone that was in use and is making a loud notification sound • Misplaced furniture, as with a tipped stool beside a body • Cigarettes, lit or remains piled in ashtray • Tool marks in unusual location or near entry/exit • Shoeprints and/or fingerprints • Drug paraphernalia Include the time that photographing was begun and completed in the notes. Remove the film or download the digital images and store in a secure location according to departmental regulations. Close-up Photographs Photograph fingerprint/footprint/shoeprint/tire track evidence using black-and-white film (when using film). Carefully place the ruler and camera perpendicular to each other and relative to the impression. When the photograph needs to be accurately scaled: • The ruler must be on the same plane as the impression. • The camera lens must be perpendicular (90 degrees) to the subject. • Use a level and tripod to position the camera accurately Take multiple shots with the light or flash at different angles, such as 0 degrees, 15 degrees, 45 degrees, etc., to achieve the best possible photographs.

Conducting the Scene Investigation Initial Phase - Associated Tasks:

Preliminary Organization of Thought Approach to Scene Initial Assessment of Scene Security Questioning of 1st Responding Officers Evaluate Scene Safety Issues /

Collection Phase - Associated Tasks

Re-Approach the Scene, maintaining working route Address Physical Evidence Take Mid-range Photographs of Evidence Take Close-up Photographs of Evidence Obtain Measurements of Evidence; Place Evidence on Sketch Examine Evidence Collect and Package Evidence /

Collection Phase - Evidence Security & Preservation

Secure each packaged item of evidence in your "safe area" at the scene Once return to office, place evidence in a secure, limited access locker. Record in notes where/how secured and the time. Record in notes the subsequent disposition of physical evidence from your custody: e.g., sent to forensic laboratory; sent to Department Property & Evidence Section; turned over to ......

Initial Phase - Preliminary Scene Survey

Take Overall Scene Photographs during scene survey Initiate Rough Scene Sketch during scene survey: • Can combine notetaking with sketching

Aerial Photographs

Take aerial and/or overhead photographs of a scene to show geographic relationships of locations or objects and aid identification of objects shown in other photographs. Obtain aerial photographs by taking the pictures from a helicopter or plane. News footage can sometimes be a useful source of aerial photographs. Overhead photographs, in this context, are taken from above the scene, such as from a ladder, a second story, a cherry picker; they are not taken from the sky, as from a plane. Aerial and overhead photographs must be overlapping. Remove the film or download the digital images and store in a secure location according to departmental regulations.

general considerations for crime scene search methods

The size of the lane of the search should be approximately the arms' length of the searcher. As the search of an area is completed, some marking should be made to indicate that the area has been completed. A mechanism should exist for the circumstance when potential evidence is found (e.g. who is called over, what path they should take, whether the other searches should halt moving until this finding is resolved).

Conducting the Scene Investigation Initial Phase - Preliminary Scene Survey

This scene "walk-through" provides the scene investigator with an overview of the entire scene, including the location of scene boundaries • Use systematic search process - Don't forget to look up Provides the first opportunity to recognize/identify potential evidence "Look but don't touch" / Begins the process of developing theories of the case Helps in the assessment of investigative needs Begins the process for the systematic examination and documentation of the scene Helps to determine a working route in the scene for subsequent examination and collection of evidence /

Conducting the Scene Investigation Initial Phase - Preliminary Organization of Thought

Type of Scene / Case Setting of the Scene Possible Type and Amount of Evidence Secondary Scene / Evidence Considerations Additional Resource / Equipment Needs Environmental Factors and Other Hazards /

Establish Capability: Policy and Procedures

-conduct research -develop SOPs and technical procedures -Validate Technical procedures

Establish Capability: Equipment

-identify needs -research and procure materials -conduct training/ familiarization

3 Components of Scene & Evidence Documentation

-photographs -notes -sketches

Establish Capability: Personnel

-select investigators -train investigators -assess competency

Photograph serial numbers on weapons or VIN numbers on vehicles:

1. Carefully place the ruler, camera and placard relative to the item to obtain accurately scaled photographs. 2. Place placard and ruler on the same plane as the weapon. It is extremely important, when the photo needs to be accurately scaled, that the ruler be on the same plane as the subject. The camera lens should be perpendicular (90 degrees) to the subject. 3. Position the lighting to obtain the best possible contrast and results. Take multiple shots with the light held or placed at different angles to the subject in order to achieve the best results. 4. Photograph vehicular damaged areas, the license plate and the registration decal. 5. Include the time that photographing was begun and completed in the notes. 6. Remove the film or download the digital images and store in a secure location according to departmental regulations.

photography preliminary steps

1. Upon arrival at the scene, record names and arrival times (when known) of all personnel involved, including investigators, medics, first responders, etc. 2. When applicable, include the names of those assigned to specific tasks in either the photo log or, when using a photo list, a notebook. 3. Plan the photography route. Photograph transient objects, such as bloodstains or latent prints, as soon as possible. Move from the exterior to the interior of the crime scene, and from general to specific focus. 4. The photography session should occur in an uninterrupted, systematic, focused manner. When planning the route, ask: − How did the victim or suspect arrive at or leave from the scene? − How was the crime committed? − Which items were handled? − Which items were moved? Which items are broken or stained? Have potentially flammable vapors been detected at the scene? Caution: Some photographic and flash equipment is flammable. When potentially flammable conditions exist, appropriate precautions must be taken. Note: Do not go beyond boundary markers to take photographs unless absolutely necessary. 5. Plan and prepare lighting for each scene and camera angle. The following techniques are commonly employed: a) Front lighting places the camera, lens, and flash or light source, directly in front of the object to be photographed. It is often the most appropriate type of lighting to use at crime scenes. b) Side or oblique lighting places the camera directly in front of the object while the flash or light source is placed to the side of the object to be photographed. This can range from 45 to 90 degrees depending on the subject and the shadow detail observed. Oblique lighting produces the best results for three-dimensional (3D) objects and is recommended for the following: To show details such as tool marks, surface irregularities or textures To show vehicle accident damage When photographing in closets or other small spaces When photographing polished surfaces 6. Control the use of lighting by manually changing the aperture, shutter speed settings and turning on/off flash settings. It is important to have a detachable flash, or, if the flash is not detachable, another light source.

Systematic Approach

Activities undertaken in the investigation of a scene are typically divided into three distinct phases. This approach helps ensure a thorough scene investigation in the most effective and efficient manner possible. Initial Phase Collection Phase Final Phase

Scene Disposition - Release or Hold the Scene ?

At the conclusion of the crime scene processing, the scene search officer should discuss the results of the scene processing with other investigators. This discussion should include the issue of scene disposition.

quadrant or zone search

Good for Vehicles and Defined Indoor Scenes Search technique should overlap into adjacent zones Zones can be further subdivided as needed to ensure effectiveness of search involves dividing the area to be searched into adjacent zones. The smaller the size of the zone, the more methodical the search can be. Zone searches may be done by multiple searchers per zone.

Line & Grid (Double Line) Search Techniques

Good for large outdoor scenes

spiral search method

Good for limited size, open exterior scenes; Good for interior scenes with limited obstructions Involves the searcher walking in a circular fashion from the outer point of the crime scene towards the central point involves a spiral into (inward) or out from (outward) a crime scene. A practical disadvantage with outward spiral searches is the evidence may be destroyed as the searchers move to the center of the crime scene area to begin their outward search.

Prioritize Collection of Evidence

Principle: The collection of evidence must be prioritized to prevent loss, destruction, or contamination. Policy: The investigator(s) in charge and team members shall determine the order in which evidence is collected. Procedure: The team member(s) should: a. Identify roles of the team members (e.g., scribe, collector, packager, etc.) b. Conduct a careful and methodical evaluation considering all physical evidence possibilities (e.g., biological fluids, latent prints, trace evidence). c. Focus first on the easily accessible areas in open view and proceed to out-of-view locations.

Document the Scene & Evidence:

Provide a means to refresh investigator's memory Provide a means for reconstruction of the scene Provide for expert forensic analysis Provide for outside independent evaluation Create a permanent, detailed record of the scene, the evidence found, and actions taken

Collection Phase - Evidence Packaging Label

Recommendations for Label Information • Incident / Event Number • Item Number • Item Description • Item Collection Date • Collecting Investigator Name / Initials Other Considerations • Time of Collection • Specific Location within Scene

information that should be documented

Record the time, date, name of the person who contacted the authorities, and incident information as soon as notification of a crime is received. These notes should be kept separate from the sketch. • Initial notes about the incident should answer the who, what, when, where, why and how questions. • Incident information includes: who reported the incident, when the incident was first reported, the crime scene location, a description of incident and participant names. • Gather information to use when sketching by talking to others at the scene. Record that information in the notes. • Questions that can provide valuable information include: − How did the victim or suspect arrive at or leave from the scene? − How was the crime committed? − Which items were handled? − Which items were moved? − Which items are broken or stained? • Have potentially flammable vapors been detected at the scene? (When potentially flammable conditions exist, take appropriate precautions.) • While sketching the scene, record related information in the notes. It is critical to use a systematic approach to notetaking while sketching to maintain a record of your activities and the order of sketches made. • Specify the changes made to a scene prior to sketching, such as when objects were moved or placards added. Note who made the changes and why they occurred.

Determining the Scale to use for all sketches

The usual scale for outdoor scenes is one inch equals twenty feet. The usual scale for indoor scenes is one-eighth inch equals one foot. Select which standard units of measurement will be used: metric (meters, centimeters) or English (feet, inches). An important consideration when determining the scale is fitting the scene to the sketch paper. To calculate the scale: 1. Determine the longest measurement at the scene. 2. Divide this measurement by the longest measurement of the sketch paper. The resulting number establishes the largest measurement end of the scale 3. Often graph paper is used for scale drawings. When using graph paper, assign a specific number of squares to the measurement identified in Step 2. Use this method to establish other measurements by substituting the actual measurement in place of the longest measurement in Step 1. Create a title block on the graph paper being used for the sketch in the lower right corner of the paper. The title block typically includes: • Case number • Crime type • Victim name • Name and ID# of sketcher • Name and ID# of person verifying measurements • Location of sketch • Date completed Create a legend for the sketch on the graph paper used for the sketch. Each sketch must include a legend that is specific to it. A legend identifies: • North-facing direction (usually points to top of page) • Identification symbols used for information in sketch • Sketch ID# • Scale used An accepted practice for assigning identification symbols is: • Use compass points to identify walls. • Use evidence numbers assigned to objects to identify them in the sketch. The legend will be updated after drawing the sketch to ensure accuracy and completeness, and to include: • Measurements for dimensions of rooms, furniture, doors and windows • Distances between objects, entrances and exits, bodies and persons

Taking Photos of Impression Evidence

Tire Impressions: For tire impressions, take a series of overlapping photographs showing the tire's entire circumference. Impressions on Glass: When the impression is on glass and when possible: • Protect latent prints • Position a colored card or piece of cloth that contrasts with the impression behind the glass • Include in notes that this approach was used for contrast purposes to obtain the photograph Impressions on a Mirror: When the impression is on a mirror, hold the flash to the side (oblique lighting); use a tripod to avoid being in the photograph. Dust Impressions: When photographing a dust impression or an impression in a soft material (e.g., wax or putty), use reflective lighting (also known as oblique lighting). When using reflective lighting, if detail does not appear sufficiently, block the ambient light and then experiment with positioning the light or flash in other locations until the desired result is achieved. Impressions on a Porous Surface: When the impression is on a porous surface, position the light or flash wherever the best results or contrast can be achieved, such as at a 90-degree angle from the impression.

Prioritize Collection of Evidence procedure

a. Identify roles of the team members (e.g., scribe, collector, packager, etc.) b. Conduct a careful and methodical evaluation considering all physical evidence possibilities (e.g., biological fluids, latent prints, trace evidence). c. Focus first on the easily accessible areas in open view and proceed to out-of-view locations. d. Select a systematic search pattern for evidence collection based on the size and location of the scene(s). e. Select a progression of processing/collection methods so that initial techniques do not compromise subsequent processing/ collection methods. • Concentrate on the most transient evidence (e.g., most susceptible to environmental conditions) and work to the least transient forms of physical evidence. • Move from least intrusive to most intrusive processing/collection methods. f. Continually assess environmental and other factors that may affect the evidence. g. Be aware of multiple scenes (e.g., victims, suspects, vehicles, locations). Processing one scene at a time to avoids cross contaminating these various scenes h. Recognize other methods that are available to locate, technically document, and collect evidence (e.g., alternate light source enhancement, blood pattern documentation, projectile trajectory analysis).

ensuring contamination control procedure

a. Limit scene access to people directly involved in scene processing. b. Follow established entry/exit routes at the scene. c. Identify first responders and consider collection of elimination samples. d. Designate a secure area for trash and equipment. e. Use personal protective equipment (PPE) to prevent contamination of personnel and minimize scene contamination. f. Clean/sanitize or dispose of tools/equipment and personal protective equipment between each item of evidence collection and/or scenes. g. Utilize single-use equipment when performing direct collection of biological samples.

documentation procedure

a. Review the assessment of the scene to determine the type of documentation needed. b. Coordinate photographs, video, sketches, measurements and notes. c. Photograph (see Photography section for details): • Scene utilizing overall, medium, and close-up coverage. • Evidence to be collected with and without measurement scale and/or evidence identifiers. • Victims, suspects, witnesses, crowd and vehicles. • Additional perspectives (e.g., aerial photographs, witness's view, area under body once body is removed) d. Record video as an optional supplement to photographs e. Prepare preliminary sketch(es) and measure: • Immediate area of the scene, noting case identifiers and indicating north on the sketch. • Relative location of items of evidence, correlating evidence items with evidence records. • Evidence prior to movement. • Rooms, furniture or other objects. • Distance to adjacent buildings or other landmarks. f. Generate notes at the scene: • Document location of the scene, time of arrival and time of departure. • Describe the scene as it appears. • Record transient evidence (e.g., smells, sounds, sights) and conditions (e.g., temperature, weather). • Document circumstances that require departure from usual procedures.

crime scene investigation

an organized, legal search by competent law enforcement officials to locate and document evidence and / or witnesses to a crime

Collect and Preserve Physical Evidence:

• Document Evidence • Use best practices to Collect Physical Evidence • Use appropriate evidence packaging techniques to Preserve Physical Evidence • Initiate and maintain Evidence Chain of Custody /

Protect the Investigators:

• Ensure scene is free of environmental hazards • Ensure scene is free of other potential threats • Consider use of Personal Protective Equipment to reduce exposure to biological hazards and to minimize cross contamination, particularly at scenes involving human tissue and/or body fluids /

Photograph bloodstains or other bodily fluid stains using

color film or digital camera. Carefully place the camera plane perpendicular to the plane of the stain and ruler. Stay alert to the location of the bloodstains, so equipment isn't inadvertently touched to the stain. • It is extremely important that the ruler be on the same plane as the impression. • If the stain is on a wall, use an adhesive label with a ruler on it. Otherwise, tape a ruler beside the stain, or have an assistant hold the ruler beside the stain. Indicate upward direction. • Ensure that the camera lens is perpendicular (90 degrees) to the subject. Adjust lighting when photographing the stain to obtain the best contrast and result. • When the stain is on glass, position a colored card or piece of cloth that contrasts with the stain behind the glass, making sure to protect latent prints; include in the notes that this approach was used for contrast purposes to obtain the photograph. • When the stain is on a mirror, hold the flash off to the side (oblique lighting) and use a tripod to avoid being in the photograph. The camera will show in the photograph when the mirror is 90 degrees from the lens.

Perspective Sketch

contains a vanishing point and depicts objects of evidence as they would appear to the eye with reference to relative distance and depth

The polar coordinate method

is more appropriate for an outdoor scene in which only a single fixed or reference point is present. Measure both the distance and direction (angle) an object is from a known reference point. The angle can be measured with either a large protractor or an optical device such as a transit or a compass. The protractor technique with a 360- degree protractor is useful for underwater scenes

The transecting baseline coordinate method

is used to measure items of evidence when there are numerous objects in the crime scene and other measuring techniques will not work. This is accomplished by laying a tape measure down so that it crosses the entire room or area to be measured. This first tape measure becomes the baseline for all other measurements in the crime scene. Measurements are then made perpendicularly from this tape by laying another tape measure at a 90-degree angle to the first tape and measuring out to the evidence.

The detailed sketch

is used when describing a small area that is not easily incorporated into the overall drawing due to the scale chosen for the rough or finished scale drawing. This is especially useful for large crime scenes.

The schematic sketch

is used when it is desirable to represent a sequence of events such as following the trajectory of a bullet through a crime scene location

The rectangular coordinate method

is used when measuring the distance to an object from two mutually perpendicular objects, such as walls that meet at a 90-degree angle.

Initial Phase: Response

preliminary organization of thought arrive and obtain basic information secure and protect scene *establish lawful authority to search* ------- conduct initial scene survey and documentation recognize/ identify evidence develop working theory

The collection of evidence must be prioritized to

prevent loss, destruction, or contamination

final phase: scene wrap up

secure evidence and equipment discuss findings with detectives final walk through

final phase: scene processing

specialized scene processing obtain overall measurements obtain supplemental photographs

Contamination control and preventing cross-contamination at single or multiple scenes is essential to

to maintaining the safety of personnel and the integrity of evidence.

It is essential to a successful investigation to select a team of trained personnel to perform scene processing, based on the

type of incident and complexity of the scene.

A projection sketch

usually contains only one viewpoint and depicts objects on one plane. The overview sketch (of the horizontal plane) is the most common type of sketch and is usually done from a bird's eye view; it shows the floor plan. Less common is the elevation sketch (of the vertical plane), which shows a side view typically of landscapes or buildings One extrapolation of the projection sketch is the "Exploded" view sketch that contains more than one wall from one viewpoint. It combines the overview and elevation sketches.

Sketching Equipment Needed

• Graph paper • Paper • 50- to 100-foot retractable measuring tape • 1000-foot walking wheel • Folding rule • Ruler • Oversize clipboard with storage pocket • Eraser • Magnetic compass • Personal protective equipment (when needed) • Flashlight • Notebook • Pencil The accuracy of all measuring devices should be ensured by comparison to a measure of certified accuracy, such as a NIST traceable ruler.

photography equipment needed

• Personal protective equipment • Camera: 35mm and/or digital single-lens reflex (SLR) of 12 megapixels or greater recommended (a backup camera is also advisable) • Several rolls of color film and black-and-white film, if using film camera • Battery backups • Memory cards for digital cameras • Detachable flash or additional lighting • Flashlight • Tripod • Camera cleaning supplies • Pen • Notebook • Evidence placards • Rulers

Basic Aspects of a Scene Investigation:

• Secure Scene / Protect Evidence • Protect scene investigators • Survey the Scene • Identify / Recognize Evidence • Document Scene and Evidence • Collect Physical Evidence • Preserve Physical Evidence • Submit Physical Evidence for Scientific Analysis

When recording video:

• Use slow camera movements such as when panning and zooming. Before zooming, stop filming, zoom, focus, then start the filming. • Use the tripod whenever possible. • When recording a long, narrow area, such as a side yard or train tracks, use a tripod and slow zooming unless using it will disturb either the scene or other team members. Always avoid walking while recording a long, narrow area. • A high camera angle, such as with an overhead view, may be required to show individual objects that are on similar planes. • Record entry/exit points from all possible angles. Show any paths used during the crime. Move to the interior and take overall, midrange, and close-up video. When recording interiors: • Always use slow camera movements such as when panning and zooming. • Use a tripod whenever possible, even though it takes more time to set up, unless using it will disturb either the scene or other team members. • When recording overall video in tight spaces, such as closet or bathroom, use a high camera angle from a corner. • When recording a long, narrow area, such as a hallway or porch, use a tripod and slow zooming. Always avoid walking while recording these shots. • When necessary and possible, use artificial lighting to get the best possible clarity. • Consider using a blue filter over artificial light to achieve similar lighting as daylight. Complete note-taking. Include in the notes such items as events that occurred while recording and the time recording was completed. Remove the videotape from the camera or download the digital video before storing the camera in a secure location according to departmental regulations


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