This article will give you my take on an what you should consider documenting when you inspect the scene and vehicle for reconstructing a rollover collision. To my lawyer friends, these lists are intended to help accident reconstructionists - they are not must-do lists for you to use against us! To my accident reconstruction friends, I would love to hear what you think is missing from these lists. Just leave your additions in the comments.
Also, I will be teaching a course on rollover reconstruction in July. Information is linked here: http://training.sae.org/seminars/c1502/. I'm hoping to have my book on rollover reconstruction done and printed by then. The course will include a free copy of the book.
Here are the checklists:
Site Inspection Checklist
The evidence that will be documented during a site inspection will depend, in part, on what issues you are analyzing and on how much time has elapsed between the crash and your inspection. For the sake of completeness, the list that follows assumes that your site documentation is taking place before any evidence has deteriorated.
☐ Take overall photographs of the accident scene. Typically, this will involve starting at the beginning of the physical evidence (initial tire marks from the loss of control, for instance) and walking along the full trajectory of the vehicle, taking photographs along the way. Aerial photography taken from an unmanned aerial vehicle can also be useful for overall documentation of the accident site.
☐ Map the physical evidence from the crash. Mapping will typically be accomplished with a total station or a laser scanner, though image-based scanning could also be used.
- Tire marks
- Gouges and scrapes
- Glass debris
- Ground impact marks
☐ Map the scene geometry.
- Roadway striping
- Vegetation and Trees
Vehicle Inspection Checklist
The evidence that will be documented during a vehicle inspection will also depend on what issues you are analyzing. Your checklist for any particular case may have more or less items, depending on the issues you are analyzing.
☐ Take overall photographs of the vehicle. Typically, a set of overall photographs would consist of 8 photographs – one taken from each side of the vehicle and one take from each corner of the vehicle.
☐ Document the vehicle identification number (VIN) and placards.
☐ Document the damage to the vehicle, taking photographs with a wide range of zoom levels. While documenting damage to the vehicle, determine if the damaged condition of the vehicle was altered during the efforts of emergency personnel to extract occupants after the crash.
☐ Document the tires and wheels of the vehicle.
- Write down or photograph the tire sidewall information from all four tires.
- Measure the tread depth of each tire.
- Measure the tire pressure of each tire.
- Photographically document damage to any of the wheels.
- Photographically document any evidence of contact between a tire and its wheel well.
- Photographically document any asphalt or soil deposits in and around the wheels and tires.
☐ Document the windows of the vehicle.
- Identify which windows are broken out and which are still intact.
- Identify which windows were up and which were down at the time of the crash.
- For windows that are broken, take thickness measurements of glass fragments still present on the vehicle.
- Document which windows are tinted and which are not.
- Document which windows are constructed of tempered glass and which are constructed of laminated glass.
☐ Document the body panels of the vehicle.
- Identify scratches on the body panels. Use tape to document their direction. This tape will help to make the scratch directions more apparent in the photographs you take.
- Some investigators use a different color tape for each scratch family on the vehicle. This can be problematic since it may not apparent, simply from visual inspection of the vehicle, which scratch marks on the various body panels are related. We recommend using a single color of tape for the various scratch marks so that the process of separating these into particular families can also take into account the site evidence and characteristics of the speed and roll velocity curves that result from analysis of the evidence.
- The order of overlapping scratch marks on the vehicle can often be determined in the field. If this is the case, one could apply the tape to the vehicle along the scratch directions in the same order the scratch marks were deposited during the accident.
- After you have marked the scratch mark directions, take another set of overall photographs of the vehicle.
- Take close-up photographs of the scratch marks on the vehicle, as well. Progress through these photographs in such a way that it is clear what part of the vehicle is being photographed. For example, to photograph scratches on the passenger side door, begin with a zoomed out photograph of the passenger side of the vehicle and progressively zoom in to a close up of the scratches. The progression from photograph to photograph will make it clear what part of the vehicle is being photographed in the zoomed in views.
☐ Document the contents of the vehicle.
- Oftentimes, vehicle components that separated from the vehicle during the crash will be placed inside of the vehicle when the vehicle is removed from the scene. Removing these components from the vehicle and documenting damage and scratch marks on them can yield additional evidence for the reconstruction.
- Documentation of the vehicle contents may also reveal what cargo was in the vehicle at the time of the crash.
☐ Map the post-crash damage to the vehicle. Oftentimes, this will be accomplished with a laser scanner. However, other techniques are also available, such as image-based scanning.
☐ Image the data from any Event Data Recorders on the vehicle.