Physical and Photographic Evidence
Evidence is gathered for three primary reasons:
- To establish accident sequence
- To provide documentation to support the investigation
facts, findings, and recommendations
- To identify causal and contributing factors
NOTE: Physical and photographic evidence gathered during
accident investigations may be used in other official
proceedings (administrative, civil, and criminal) and must be
collected and processed correctly to maintain the integrity
of the evidence. Generally the team’s law enforcement
representative is the most qualified individual to do this.
Physical Evidence Preservation
The chief investigator should determine what evidence
is fragile or perishable and may be destroyed or lost due to
weather or theft, or moved, in order to protect valuable
equipment or evidence. This may require increasing the
security personnel, expanding the site security perimeter,
covering the site with plastic, obtaining a secured facility, or
carefully packaging and removing evidence.
The chief investigator should, with cooperation from the
law enforcement representative, establish:
- What evidence needs to be gathered.
- Procedures to be used.
- Who will gather the evidence.
- The evidence and chain-of-custody logs.
- Where evidence should be stored.
Physical evidence, such as equipment and parts, need to be“
bagged and tagged” at the time of collection. Large items,
such as vehicles or construction items, should be secured.
The law enforcement representative will establish logs for all
ground accident evidence. It is imperative that all evidence
be cataloged and accounted for at all times. Some evidence may be perishable if not collected as
soon as possible. The originals or a copy of important
documents (evidence, potential evidence) should be placed
in the investigation case file.
All aviation accident evidence gathered during aviation
accident investigations will be maintained by the NTSB.
Types of Physical Evidence
There are three principal types of physical evidence: Human, material, and
Human evidence includes:
- Training records
- Qualifications and certifications
- Time and attendance records
- Dispatch logs
- Risk assessments (JHAs)
- Witness statements
- Policies and procedures
- Medical records and test results
- Autopsy and toxicology reports
- Autopsies can provide valuable information to the
accident investigation team. The rules for autopsies
vary from State to State. Most States require an
autopsy if the death was not attended by a physician.
- The team
leader or the law enforcement representative should determine if an autopsy
will be conducted. If so,
request analysis of samples of body fluids.
- If an autopsy is not
planned, determine whether the family would agree to one if the information
benefit the investigation.
- Firefighter Autopsy Protocol: Firefighter
beneficiaries will normally receive a death benefit only if an autopsy
is completed. A waiver may be given on a case-by-case
basis. The team leader should ensure that the medical
examiner has a copy of this protocol.
Material evidence includes:
Environmental evidence includes:
- Weather reports
- Weather damage analysis
- Terrain analysis
- Environmental hazards
- River volume and flow
- One of the most useful tools the investigator can bring to
the accident scene is a camera. The camera shows the
view seen by a witness and can record documents. Digital
cameras (3 or 4 megapixels) and cameras that process their own film are ideal
for this application. Film from 35
millimeter cameras can be converted to digital format if
- While videocameras have their uses, photographs may
be more useful because they can be enlarged, printed in
multiple copies, and placed in the factual section.
- Depending on the accident’s complexity, a professional
photographer may be needed.
- Photographs do not have to be taken in the order the
investigator intends to look at them. Shoot all the distant and
medium shots first. Those shots can be taken with a handheld
camera without extra equipment. Afterward, take closeup
shots with a tripod, flash, or cable release. This method saves
time because you do not have to switch back and forth
between the two types of photography.
- Basic Types of Documentary Photographs.
- Perishable Evidence. These photographs document things
that are likely to change or disappear if not photographed
immediately. Such photographs may include shots of an
accident’s aftermath or a rescue in progress, gauge readings,
ground scars, radio settings, fire damage, and the positions
of switches on equipment.
- Aerial Views. When performing aerial photography,
photographers need an aviation plan, approved by the unit
aviation officer. If possible, photograph aerial views early.
The appearance of the accident site from the air will change
rapidly as investigators move through it. Important locations
on the ground can be marked with yellow flagging or other
suitable material (for example, a yellow fire shirt). Shoot
from different angles and at different altitudes.
- Overviews of the Scene. Photograph the equipment
wreckage at the accident site from the eight points of the
compass (N., NE., E., SE., S., SW., W., NW.). If the accident
scene is spread out, try a series of overlapping pictures. The
prints can be matched at their edges to create a panoramic
- Significant Scene Elements. Try to establish the terrain
gradient through photographs. Photograph ground scars to
record information that will allow their size and depth to be
analyzed in the future.
- Site Inventory. Photographs can help inventory the accident
site and document personal protective clothing equipment
and other safety equipment, including the victim’s personal effects
and clothing. The location of each item may be
plotted on a scaled map using a fixed point of reference.
- Closeups. Bracket exposures for closeups by taking two
photographs with slightly different exposure adjustments (fstop
and shutter speed). Use a tripod or monopod, as
- Documents. Photographs can be used to record documents
that cannot be retained. Such documents include licenses
and logbooks, or maps and charts.
- Witnesses’ Views. It may be important to document the
witnesses’ views of the accident. Because the witnesses may
have had wide-angle views, use a tripod and the panoramic
technique to duplicate the views with photographs.
- Exemplars. An exemplar is a model or a pattern for an
actual object. Sometimes it is difficult to tell from a wreckage
photograph what the part or component is supposed to look
like. In some investigations, it is important to have pictures of
an identical undamaged part or component for comparison.
- Wildland Fire Photos. In addition to the types of photographs
previously discussed, the following photographs are
needed for fire management accidents:
- Final resting position of victims, equipment, trees, and
other relevant items.
- Fireline construction at the accident site.
- Equipment carried or worn by personnel (personal and
- Firefighters’ personal protective clothing and equipment.
- Safety equipment.
- Vegetative conditions (before and after, if possible).
- Surrounding terrain, structures, and orientation.
- Fire origin and buildup.
- Shelter deployment—shelter, packaging, and the position
(side, back) where it was carried.
- Incident command post facilities or equipment.
- Presentation. Photographs used in the factual section
should be mounted and have captions attached. An
example of a documentary caption would be: “View of
damaged driver’s door looking north.” Each photo should
include the name of the photographer and the date the
photo was taken.