Reconstructionists Play Pivotal Role At Remote Crash Scenes

Vehicular accidents unfortunately don’t occur in just one locale. They strike every hour, on the hour, in the most populous areas of a state as well as in the remotest. The challenge is that the more remote the accident scene, chances are high that the expertise needed to fully investigate crash scenes will be sparse. Nevertheless, most cases involving a crash usually end up in court, making it essential to examine the crash scene thoroughly and generate a detailed diagram that will present the most likely sequence of events for a jury.


Almost invariably, well trained reconstructionists investigate and document crash scenes, but usually not far from their base of operation. When accidents occur in remote parts of a state, the investigating officer or team may not include a reconstructionist. Since the scene still must be investigated, mapped and diagrammed, these documentation steps can be more challenging.

State patrols across the country tend to encounter this dilemma more than other law enforcement agencies such as police departments and county sheriffs. The more remote a state patrol’s districts, the fewer troopers there are to patrol highways. When a crash occurs, it’s a pretty good bet that the responding trooper will not always have the skill, knowledge, confidence or equipment that a reconstructionist would offer.

For this reason, reconstructionists, particularly those serving with state patrols, are becoming more mobile, making themselves available to respond to crash scenes that may be hours away from their offices. Crash Reconstruction Specialist Duane Meyers, Wisconsin State Patrol—NE Region, for example, notes that troopers often bring forward information on their crash cases, after which he or other reconstruction specialists create a detailed diagram. They also travel to distant crash scenes to assist with investigations, which can involve driving up to five hours.

Guidance, Coordination Brought To Crash Scene

Part of the value which trained reconstructionists bring to a crash investigation is their pure length of service and experience. “They often have more resources available because they’ve purchased equipment beyond what their state has provided,” explains Meyers. “As reconstructionists, we make every effort to get all of the available information,” Meyers continues. “And we’re dedicated to documenting every item that has evidentiary value.”

Since every crash is different, Meyers believes it’s important to consider three basic factors when approaching the investigation: human, environmental and vehicle.

  1. The human element considers at least a one-week history of the driver, what kind of work he was performing, how much work he did, when the work was accomplished, when he slept, as well as any substances that he might have consumed that may have subjected him to impairment behind the wheel.
  2. Environmental factors include roadway design issues (i.e., vertical and horizontal curves), signing, climate or weather conditions, lunar positions of the moon and sun, and pavement conditions.
  3. Finally, mechanical issues such as brakes, suspension, gear position, engine condition and general safety of the vehicle’s systems must be considered.

Meyers views the process of crash scene reconstruction as a team effort, requiring leadership and experience, noting “We’re comprehensive about our data collection.”

Scene Complexity Requires Strong Reconstruction Skills

If you don’t routinely investigate crash scenes, as is the case for many state troopers, just determining the details to document can be overwhelming. “They might not know the best way to tackle a particular problem,” notes Corporal Dave Templeton of the Florida Highway Patrol. For example, Templeton continues, “If you have cars bouncing off of multiple cars, and the investigators are trying to get an accurate representation of the energy involved, this may be a little beyond their training.”

Troopers have the basic skills to investigate a crash scene, yet crash reconstruction is something they don’t deal with every day. Many times they don’t feel that their diagrams can stand up in courtroom, which is why troopers often will consult with reconstructionists about special issues.

Mapping Tools Used

A big advantage that reconstructionists have over troopers who can conduct basic crash scene investigations is that they are techno-savvy. One common tool, of course, is the ubiquitous total station used for plotting key data points at the scene so a diagram can be created. The total station used for years by law enforcement officers and reconstructionists, can map data points for very long distances, and is ideal for large crash scenes. Laser-based speed and measurement instruments represent another frequently used technology that has emerged in recent years. Still another technology recently gaining more acceptance among reconstructionists is photogrammetry, which involves special software used with a digital camera that captures crash scene data points in 2D or 3D, then stores them electronically. There is far-range photogrammetry (with camera distance setting to indefinite), and close-range photogrammetry (with camera distance settings to finite values). Special photogrammetry software, like iWitness by DeChant Consulting Services, of Bellevue, Washington, is used to obtain 3D coordinate data from a series of markers placed at a scene and photographed from different angles. Then, by exporting the data points from iWitness into a diagramming software program, a very detailed and to-scale 3D diagram can be generated.

Scaled, 3D Diagrams, With Animation, Tell Whole Story

Both troopers Meyers and Templeton are long-time users of The Crash Zone diagramming software because of it’s easy to use yet very powerful. The Crash Zone was their choice because it is tailored so well to the reconstructionist’s needs for creating detailed and accurate 3D drawings. For example, the software offers extensive drawing and editing features, thousands of pre-drawn vehicle and crash scene symbols, 3D views and animation tools, the ability to import 3D data points from Laser Technology devices and total station systems, and number of crash calculation tools.


3D Crash Scene drawn with Crash Zone

Corporal Templeton and his fellow Florida Highway Patrol reconstructionist team all use computers in their cars. The Crash Zone program is on each computer. “It’s a wonderful tool, and the learning curve is far less than for anything else we’ve used,” notes Templeton. In addition, he said, “I can shoot my scene and show what the grade and elevation of the road is, plus the height difference between two points.”

Whenever a scene involves a major crash with injuries or fatalities, it’s going to be a complex one to investigate. For scenes matching this description, the high-level expertise of a seasoned reconstructionist is essential. That’s how Trooper John Howell with the Nevada State Patrol views it. He is part of a reconstructionist team that works out of the southern command in downtown Las Vegas. Reconstructionists may travel up to 280 miles away three to five times a month to help investigate a complicated crash scene. Whether the scene involves a tourist bus carrying 50 people, or it’s a one-person accident resulting in a pile-on in a construction zone, “Any of these will get our attention,” says Trooper Howell.

When Howell’s crash detail arrives at a crash scene in a rural area, the scene has been stabilized by the troopers who originally responded to the call. From here, the detail takes over the investigation of the crash, mapping and photographing the scene, determining needed evidence points, and even visiting the hospital to visit with survivors.

Roughly 85 percent of crashes in Nevada go to court, while the remaining 15 percent are pled. For the court crash cases, diagrams typically tell the whole story. In addition to creating the diagrams in 3D, Howell notes that animation, which soon will be added to them, will make a huge difference in how the events prompting a crash, along with its aftermath, most likely played out.

“When you’re dealing with a layperson on the jury,” explains Howell, “it’s easy to overwhelm him with facts and figures that he can’t see happening. He doesn’t see the vehicles, or the collision that occurs. When you can actually animate this and bring a scene to life and show the juror literally a moving picture, or a moving simulation of what occurred at the scene, it makes it a lot more intimate and allows him to make much more informed decisions.”

Contributed by Bob Galvin, a Portland, Oregon freelance writer who writes on topics covering technology used by law enforcement to investigate crime and crash scenes.