Crime Library: Criminal Minds and Methods

Point of No Return: The Case of Peter Bergna

Accident Reconstruction

Many police officers are quite sophisticated in methods of accident reconstruction. From road skids, the car's condition, weather conditions, and other factors, says Donald van Kirk in Vehicular Accident Investigation and Reconstruction, they can accurately determine just what happened. To come up with accurate calculation of what happened between two vehicles or a vehicle and an object, the first group will note several key items, such as pre- and post-impact skid marks, lighting and conditions, the final positions of the vehicle or vehicles, the type of damage to the vehicle, and the tire condition. They'll take verbal reports from the drivers, if possible, but will rely on the more objective interpretation of engineering to get a final result. Key elements to be determined are speed, distance traveled (pre and post-impact), and lapsed time, using simple momentum and energy calculations.

To determine responsibility, investigators will also learn what they can about the mechanical condition of the vehicle, and will note any contact mark between one vehicle and another or an object (in this case, a guardrail). They will also collect eyewitness accounts (only Peter's was available), figure out what to expect in terms of performance from the vehicle models, and note the date and weather conditions of the accident. Another factor will be the driver's history. These all go together into a file in the event that litigation will follow. The best information is the vehicle itself and where it came to rest. Thus, investigators often work backwards to establish the incident chronology, including all other known facts. Then an engineering analysis is done to derive the speed at which the vehicle was traveling. This can be compared against available eyewitness reports.

Some reconstructionists say that unless a computer simulation is used, the calculations will not be scientific. Controlled crash tests are not accurate renditions, and hypothetical models that are untested fail to meet scientific criteria. The computer will duplicate the physical laws of motion and apply them with precision to the facts about the vehicle and the incident. A 3-D animation is the best tool available for seeing and working with the totality of the circumstances. But such tools are devised only when there's reason to believe a case is going to court. No one yet knew if that would be the case in the Bergna incident.

Officer John Schilling
Officer John Schilling

Over a year after the crash, Officer John Schilling, who had been on the scene that night and was an accident reconstructionist, acquired a Ford truck similar to Bergna's to try a partial re-enactment. He and other officers drove it down the road and around the curve at varying speeds, finding that even at a fairly quick clip, there was no reason why Peter Bergna could not have maneuvered his car safely away from the guardrail and the precipice beyond. In fact, Bergna's account of what happened made little sense, unless he made a sharp right turn into the guardrail. They videotaped their efforts, just in case.

Schilling reported that in his opinion, according to Mike Henderson in the Las Vegas Review-Journal, the truck brakes had not failed and Bergna had gotten out of the car before impact with the guardrail. He found no skids on the road to indicate someone hitting the brakes or even swerving to try to avoid hitting the rail. It appeared to be a staged accident, and therefore a homicide. Still, it would be another year before any action was taken.

In the fall of 2000, Chief Deputy District Attorney Dave Clifton listened to the evidence gathered thus far and decided to take the case to a grand jury. The members convened on November 15.

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