0567-2806-MTDC: Accident Investigation Guide, 2005 Edition: Chapter 4

Accident Investigation Guide: 2005 Edition

Chapter 4—Physical and Photographic Evidence

4.1 Physical Evidence—General

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.

4.2 Physical Evidence Preservation and Collection

The chief investigator or QTI must 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 or QTI will, 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 (exhibits 4–1 and 4–2). 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.

4.3 Types of Physical Evidence

There are three principal types of physical evidence: Human, material, and environmental.

Human evidence includes:

Training records
Qualifications and certifications
Time and attendance records
Dispatch logs
Risk assessments (JHAs)
Briefings
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 gained would 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:

Equipment
Tools
Machinery
Vehicles

Environmental evidence includes:

Weather reports
Weather damage analysis
Terrain analysis
Environmental hazards
River volume and flow

4.4 Photographic Evidence—General

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 developed correctly.
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.

4.5 Photographic Documentation

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.
1. 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.
2. 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.
3. 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 view.
4. 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.
5. 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.
6. Closeups. Bracket exposures for closeups by taking two photographs with slightly different exposure adjustments (fstop and shutter speed). Use a tripod or monopod, as appropriate.
7. Documents. Photographs can be used to record documents that cannot be retained. Such documents include licenses and logbooks, or maps and charts.
8. 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.
9. 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.
10. 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 official gear).
  - 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.
11. 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 (exhibit 4–3).