Scientific testing and re-enactment

Finding new puzzle pieces.

Scientific testing.

Solving a complex injury analysis scenario is very similar to solving a jig-saw puzzle in order to finally see the image revealed. You need to look for pieces of the puzzle, and then fit them together in order to see the big picture. In forensic injury analysis and accident reconstruction, the pieces come in many shapes: Witness statements, police and OSHA reports and photographs, testimony, surgical, MRI and CT reports, weather and moon historical records, dimensions of machinery, skid mark length, event data recorder downloads from cars/trucks/locomotives, autopsy reports and photographs, train consist reports, depth of vehicle crush, vehicle steering gear ratio and manual transmission shift pattern, surveyor's field drawings, blood spatter in a car, surveillance video, railroad crew audio transmissions, site inspection, interviews, slack adjuster lengths and cell phone records. Of course every case is unique and certainly not every case would contain all of these elements, nor is it always necessary to obtain these pieces of information. In fact, challenging forensic cases are specifically difficult because there are not enough pieces to put together in order to solve the puzzle.

Fork lift accident
By using exemplar vehicles, the tasks that both operators were doing were re-created.

Dr. Strauss has 30 years of experience designing and conducting scientific tests. Careful planning, conducting tests using scientific and repeatable methodology, and thorough analysis of the resulting data can provide the additional necessary puzzle pieces in order to solve the problem. A major bonus to performing testing, if planned properly, are the resulting photographs and video recordings that show how the real world operates, not how a computer simulation operates. Photographs and video recordings of the tests and re-enactments are extremely potent tools with which to teach the trier of fact. Pictures speak a thousand words. How many words does a convincing video speak?

Jurors are often skeptical of a talking head; many don't understand computer simulations of which the output is only as good as the input data. But a well-constructed video documenting the test methodology, set-up, performance and results is very easy for a juror to understand, and very difficult to successfully cross-examine. Years of experience in conducting scientific tests and re-enactments is just another potent tool Dr. Strauss possesses to aid in his accident reconstruction and injury causation analysis.

30 years of experience designing and conducting scientific tests.

Vehicle turbulence

Can air turbulence of a passing truck suck in a nearby pedestrian? That was the question posed when a child was struck and injured by a passing truck. This scenario was researched and the literature was silent on this topic. Since there were no witnesses or video surveillance cameras, how was this question answered? By renting an airport runway and having a custom mannequin fabricated. A large number of tests were conducted with the truck driving at different speeds and distances from the mannequin while data was collected from air speed sensors adjacent to the mannequin. The results were conclusive — air turbulence created from the truck could not have blown over the pedestrian. This was also the impetus for further air turbulence testing on a large variety of vehicles. The results were published as an SAE journal article and selected to be published in a Special Publication on pedestrian safety.

Nighttime illumination of pedestrians

If a pedestrian is struck while crossing a street at night and the driver says "I was paying attention and did not see him" one of the things that can be measured is the amount of illumination at the accident site. Planning would involve first researching the location and phase of the moon on the night of the collision. Then determining if the artificial lighting had not changed. The last step is to conduct measurements on a night with the same moon illumination. The results can then be compared against accepted norms.

How did the scissor lift fall over?

A scissor lift and fork lift truck were being operated in the same building. Somehow, the scissor lift fell over and nobody could explain how it occurred. By using exemplar vehicles, the tasks both operators were performing were re-created. The results showed that even with the fork lift stationary, the fork lift operator activated the sideways movement of his tines which inadvertently went under the scissor lift. The next time the fork was raised, the scissor lift went over.