Transcript Forensic Archiving II

Forensic Aspects of Photography
Although forensic photography is simply the application
of photographic principles to forensic situations, proper
archiving includes rules that are inviolate.
Invariant Rules of
Forensic Photography
 The first photograph in a series must have an incident
photographic worksheet or cover sheet
 Photographs must be listed in a photo log
 Camera settings – date – case number – initials –
evidence numbers.
 Types of Forensic Photographs:
 Establishing, midrange and close-up photographs
Invariant Rules of
Forensic Photography
 Illumination (metering) should be appropriate to capture impression
evidence detail.
 Tripods
 Tripods should be used for all photographs where the camera must be
steady: close-ups, certain mid-range photos, Luminol (BlueStarTM)
photography and dim light situations.
 The camera (and tripod) should be perpendicular to the plane in which
the evidence lies and horizontal (parallel).
 Photographs should be taken before and after each on-scene manipulation
(enhancement attempts) of evidence.
 The pop-up flash on the camera should never be used except in specific
circumstances.
Scene Incident Photographic Worksheet
 The scene incident photographic worksheet is
the cover for a book or series of photographs.
 Not the same as the photographic log
 The cover sheet for a set of scene
photographs that are listed in a photographic
log.
 The Photographic worksheet has specific data
that includes the date, time, agency, case number
and the name of the photographer.
 Has color stripes for determining whether
the camera is “seeing” colors correctly.
 Can have scales for estimating size
Photo ID Cards
http://www.forensicssource.com/ProductDetail.aspx?
productName=1005949&CategoryName=
Crime-Scene-Documentation-Photo-ID-Cards
Photo
Log
List of all the photographs taken in a specific series.
 Each entry contains the specific photographic and forensic
information needed about that specific photograph:
 Camera settings, description of what the photograph was and
the type of photograph – establishing, midrange, close-up.
 Can have other case-specific information.
Critical Forensic Photographs
 Forensic investigations require complete coverage.
 Archiving is critical to that process
 Archiving must cover the entire crime scene as though
making a documentary.
 Means capturing landscape and close-up photos
 Forensic Archivist must be an expert in recognizing
evidence at the crime scene
 AND capturing it in the three principle photographic
types: establishing, midrange and close-up.
Critical Forensic Photographs
Category of Photograph
Establishing
(Overview)
Reason for the Photograph
Continuous, overlapping perspective of the scene.
No scales are necessary.
Maximum depth of field (f/11-22).
Depict the general orientation of the scene
Establish the relative position of evidence
Midrange
Capture the immediate surroundings and relative relationship of
items of potentially probative evidence.
Scales may be necessary depending on subject. If so,
photographs should be with and without scales.
Maximum depth of field (f/8-16).
Close-up
(Macro Photographs)
Capture detail of potentially probative evidence. Photographs
with and without scales.
Shallow depth of field (f/1.4-4).
Perspective in Midrange Photographs
 After the establishing photos, the next step is to “get closer” to
the evidence photographically so that its relative position in a
specific area of the scene is made clear.
 Establishing shot shows knife lying some distance from the
deceased’s outstretched right arm.
Midrange shots pinpoint knife’s position perfectly, which could
require more than a single photograph encompassing multiple
perspective
 From the deceased’s feet, from the outstretched right arm, looking
from the knife to the outstretched arm, from the left and right sides of
the deceased, from the deceased’s head, from all doorways if they not
too far away … etc.
 Knife’s position relative to the doorway, the deceased and
other rooms is preserved - archived.
Midrange Photographs
 A single bloodstain pattern at a scene should not present
an archiving problem, but multiple bloodstain patterns should
be labeled sequentially … specific designation different from
other tagged evidence.
 If most of the evidence at the scene is tagged as, say, items
1-99, the bloodstain patterns could be tagged using alphabet
markers, such as A-Z.
 Scales should be present in all bloodstain pattern
photographs. Flash should never be used for bloodstain
patterns.
[1]
Gardner, Ross A. ibid, page 147. Attribution to Toby Wolson
Close-up Photographs
 All Evidence having detailed
investigative value –
 Knife length and width - must be
preserved photographically.
 Pattern evidence: Fingerprints,
footwear impressions, tire
tracks, tool marks, etc.
 1st photograph taken without
scales …
 2nd second with scales.
 The scales must also be
appropriate:
o A fingerprint requires
millimeter scales
o knife on the floor does
not require that much detail
and can be photographed
using an inch ruler.
Close-up Photographs
 Use tripod because any movement blurs or obliterates
critical evidentiary detail.
Rule of Thumb for Close-up
photography?
 The rule of thumb:
 Any evidence that will not be removed from the scene
that has direct comparative value
 Any evidence that has potential comparative value
DoF: Close-up photographs are absent DoF
 Photographer opens the aperture and concentrates
on focus
 Fill LCD viewfinder with the image of the evidence.
Evidence Archiving
Illumination
 The relative position and type of light entering the camera.
 Location of the light source.
 The type of light refers to a flashlight or IR, UV, or light from an ALS.
 Alternate light sources (ALS) are indispensible tools for highlighting
important items of evidence.
 Varying wavelengths of light can visualize small items of evidence
(microscene elements).
Light Interacting With Matter
Object Fluoresces
Light
Source
(White - ALS, UV, IR)
Reflected Light
Eye
Object
Or
Camera
Light
Absorbed
Reflected
Transmitted
Barrier Filter
Barrier Filter Blocks Reflected Light
Barrier filters are different colors depending on wavelength of light
Reflected Light can
Mask the fluorescence.
 Barrier filters.
 Block reflected light so it never gets it to observer (camera
and/or person).
 The orange goggles used in CSI are barrier filters that
block the reflected light
When blocked, fluorescent light enters the camera and is
“seen” by the digital sensor and the photographer,
 Goggles of an appropriate color are necessary
 Orange
 Red
 Clear
 Yellow
Crime Scene Photo Archiving
Review
 Using tripods
 Close-ups
 Difficult shots outside – when long exposures are necessary
 Shots with scales
 Midrange
 Fast shutter speeds (< 125th or 60th with fast lens)
 Low light requiring long exposures – avoid high ISO values
 Luminol
 Fluorescent photography
 Establishing Shots:
 Maximum Depth of Field
 Small aperture (large f/number)
o Slow shutter speed
o Creates possibility of vibration movement
 Close up Shots:
 Shallow Depth of Field
Positioning the Camera at the Scene
Establishing shots & Camera Placement
Positioning the Light
Source
Direct Lighting
Camera
Camera
Camera
Light source
Light source
Light source
10 degrees
45 degree angles & one
or more light sources
Closer to Camera produces
Reflection and Glare
Reflective lighting
Highest Contrast
Light source
Transmitted
Light
Oblique Lighting
Low angle light for impression evidence:
Wet & dry residue footwear prints, tool marks, fingerprints
Camera
Camera
Light source
Light source
3D Impression
Dry Residue Print
Wet & dry residue footwear prints, tool marks, fingerprints
45deg
10 deg
Photography of Impression
Evidence
Existing Overhead
Lighting
Oblique Lighting Oblique Lighting
25Degrees
10 Degrees
Oblique Lighting
45 Degrees
Scene Types
Evidence Expected
Photographing Common
Scenes
 All crime scene investigations follow a roadmap or menu of
activities.
 Challenge: Follow precise schedule without undermining the
intellectual thought process.
 Establishing photography is one of the first activities
 Must be done logically and fit team leader’s
investigative philosophy.
 Photography is one part of the investigative puzzle.
 Not an independent activity
 Must fit the logic of the investigation
 Cannot interfere with the processing flow.
Photographing Common
Scenes
 Use logic concerning where archiving begins AND its
sequence.
 Generally, photography begins where activity took place.
 Where team begins investigative efforts.
 Where the photographer and team spends most time
o Makes scheduling difficult but critical.
 If photography happens out of phase, investigation will be
inefficient … may miss critical evidence. .
Photographing Bodies
 Photographing the body is important,
 Done properly and @ proper time.
 Dictated by how the investigation moves forward and the
involvement of the medical examiner.
 Body is part of the macroscene and is scene unto itself.
 Has critical evidence that can help close the
investigation or provide critical probative evidence.
 Blindly photographing body 1st is illogical AND not necessarily
correct.
 Not necessarily a major source of fragile evidence that
requires immediate attention
 Does not need to be removed from the scene immediately.
 Might not be where most of scene activity took place.
Defining Scene types,
With Respect to Archiving
 Certain scene types require specific considerations.
The crime types include: vehicular accidents,
homicides, sexual assaults, burglaries, hit-and-run,
suicide, arson and bombings.
 Each scene dictates the specific and necessary
archiving details.
Homicide Scenes
I: Body & Surroundings
Establishing overhead view.
Mid-range photographs of body taken clockwise – headto-feet, right arm and side, feet-to-head, left arm and
side. A tripod may not be necessary. But if the area is
dark, a tripod may be necessary.
Close-up views using a tripod– head, hands, feet,
clothing, wounds, bite marks, etc
Weapon-specific photographs
Mark the position of the body with markers. It is not
necessary to outline the entire body with chalk, just
location of head, hands and feet.
ALS photography of the body
II: Ancillary Archiving at
Homicide Scenes
Establishing photographs of the scene exterior, , e.g., from
75-100 feet. 1st shots of front of house and driveway - move
clockwise.
Depending on weather conditions, last photographs taken.
Include landscaping and impression evidence. Aerial
photographs - on-line services may be able to provide these.
Photograph looking away from the scene.
Reason for Photograph
To capture the surrounding area from an aerial view. The shot should be as
vertical as possible
Gives the perspective of the body’s surroundings.
Documents the detail of the body
This is to capture bullet holes in furniture, walls or other defects – knife marks,
etc.
Knowing the precise location of the body helps if investigators must return to the
scene. With photographs in hand and marks of head, hands and feet will suffice to
show investigators the relationship of the body to the scene.
The body should be photographed using an ALS in order visualize biological
evidence (semen, saliva etc) and fibers. It is important to do it at the scene so that
the relative location of the evidence can be seen in relation to the position of the
body.
Reason for Photograph
Establishes exterior boundaries. Could be helpful in establishing egress and /or entry
routes, possibly in retrospect.
A perspective of the area surrounding the scene from the scene’s viewpoint can be
important.
All rooms that have activity
Areas where evidence is likely located. Capturing this information critical.
Areas that do not have activity
No one knows when other, visually non-active areas of the indoor scene may shed
important evidence.
This will help provide a visual perspective of the perpetrator(s) movement through the
scene.
Impression evidence can be compared by forensic scientists with samples taken from
suspects.
Establishing, mid-range and close-ups of areas where
fingerprints are found or where it is suspected they might be
Indoors and outdoors, impression evidence must be
photographed and, it possible, lifted or cast.
Sexual Assault Cases
Sexual Assault
Reason for the Photograph
• Usual scene photography
including entrance and egress
points.
• Interior and exterior establishing
shots as in homicide
investigations above.
• Establishing photography is SOP
ALS Photography of the scene
• Locate biological & fiber evidence.
• Entrance and egress points
important - location can support or
refute victim’s/suspect’s allegation.
•Location is important to verify &
support victim’s/suspect’s
statements.
Arson Cases
The Burning Fire Scene
Reason for Photograph
• Establishing exterior shots of the fire
• External meter captures correct incident light.
• RAW files obtain the proper WB impossible with JPEG
files.
• Fires flow upward and outward from a source in a 3D
pattern.
• Establishing shots capture movement.
• External meter necessary for digital
photography,
• RAW files critical
• Photograph all sides of the burning
building WHILE burning if possible
• Establishing shots capture fire flow changing
direction when new fuel source encountered or if fire
reaches obstruction.
• May capture flashover –fire not suppressed in a
confined space can reach 1100oF & ignitable items
burn.
• Items below hot gas layer & not in direct contact with
flame will ignite & help propagate the fire.
Capture color of flames – can indicate type of material
burning but NOT temperature of the flame.
Individuals in the crowd or standing alone watching the
fire.
Arson Scenes
After the Fire is Out
Establishing exterior shots
Reason for Photograph
Identify fire-flow patterns to correlate with those taken while
the fire was burning. Elevated views help locate roof
involvement.
Difficult: Damage related to fire fighting efforts may obliterate traces of
the perpetrator(s). Identify entrance/egress points of possible arsonists.
Discarded items used to start the fire, tire tracks of non-official
vehicles, etc:
Establishing interior shots
of the fire. External meter is
necessary.
Purpose is same for any scene: to capture fire and fire
suppression activities. Indicates possible location of fire
patterns and preserves damage and position of bodies or
missing items.
Mid-range interior shots
Document char, smoke and soot patterns to understand
development of the fire flow. Damage patterns on furniture:
charring, soot, melting and the location of vertical and lowburn patterns.
Document immediate surroundings of evidence of a criminal
nature, such as bodies and accelerant patterns pointed out by
the fire marshal.
Close-up interior shots
Document fire patterns or signs indicating natural, accidental
or deliberately set fire.
Photographing Dark Areas
On-Camera Flash
Attached Flash Unit(s)
Painting with Light
Slaves
Painting with Light
http://www.diyphotography.net/painting_with_light
Special Technique
Using Slaves to Highlight Dark Areas of Scene
Arrows show Direction of Placed Slaves