Posted on September 27, 2022 at 2:52 PM by André Loyd, Ph.D. and Hernán Mercado-Corujo, P.E., .
Two decades ago, the body of a woman was found inside a burned vehicle on a farm in Iowa City. Police and fire investigators struggled to understand what happened based on the incident site, body, and vehicle evidence. In 2017, Steven J. Kline entered an Alford plea on charges of second-degree arson, willful injury causing serious injury and suborning perjury. In an Alford plea, the defendant asserts innocence, but considers the evidence too strong to go to trial.
Prior to the plea, ESi consultants Dr. André Loyd and Hernán Mercado-Corujo were asked to analyze the evidence from three different perspectives: crash reconstruction, vehicle fire origin and cause, and injury biomechanics.
To perform a speed analysis, an aerial map was used to chart the trajectory of the 1987 Mercury Sable LS (Figure 1). The vehicle exited the road going eastbound on a bidirectional two-lane road with a reduced shoulder. At the edge of the road, a gradual elevation drop led to a grass field. Obstacles to the vehicle’s travel path included two cattleguard fences; one at the toe of the slope leaving the roadway and another an unknown distance away. The terrain was semi-cut grass with near arid dirt beneath. On the downslope, the grass and weeds were overgrown.
Figure 1. Present day aerial depicting trajectory of the vehicle once it left the road.
According to police and fire department reports, the vehicle traveled approximately 740 ft. from the edge of the road to its final resting position, with the first 167 ft. sloping down an unknown grade. As with most crash reconstructions, our consultants started their analysis by working backwards from the vehicle’s final rest position. The calculated speed at the toe of the slope fell within a range of 27-32 mph as the vehicle slowed to a stop while freerolling on the subject groundcover over a distance of 573 ft. (740 ft. – 167 ft.). This assumes a relatively flat ground surface after the initial elevation drop. The freerolling assumption is based on the fact that the vehicle was found in neutral gear.
- Other than fire damage, the front of the vehicle showed a nearly pristine hood, with the frame rails exposed.
- Most, if not all, of the plastic components had melted as a result of the fire, including the headlights and bumper cover.
- Notably, there was no substantial crush damage that would indicate a significant frontal collision.
Figure 2. Subject vehicle exhibited little to no frontal crush damage
Vehicle Fire Origin and Cause
For the fire origin and cause aspect of this investigation, our consultants relied on photographic documentation and recorded witness statements. The start of the fire was not witnessed, but a nearby resident described hearing an explosion shortly before seeing a glow in the distance. Engine and passenger compartments showed the most direct fire damage, as shown in Figure 3.
Figure 3. Interior of subject vehicle post-seat removal. Steering wheel circled in red.
At the time of the photo, the front seats had been removed. The photographic evidence suggested that the fire started in the passenger compartment, particularly the front seats:
- The vehicle interior showed irregular fire patterns, particularly in the front seat footwell areas.
- The rear end of the vehicle (bumper, lights, trunk portions) was not directly affected by the fire.
- The portion of the roof directly above the front passenger seats was the only section that showed material buckling due to the intense heat exposure.
- V-patterns were observed on the front doors.
Glass from the vehicle’s four doors was found over 50 feet around the vehicle, consistent with the explosion heard by the witness. Not enough information was available to determine if ignitable vapors or some sort of delayed ignition device (i.e., M80 firecracker) contributed to the explosion.
Reports indicated that the vehicle had experienced engine coolant leaks in the past. However, the evidence did not support the theory that these leaks contributed to the start of the fire.
- While engine coolants may be among the combustible liquids used in a vehicle (commonly ethylene or propylene glycol), studies show that ignition requires very hot surfaces under specific circumstances.
- In the subject vehicle, the coolant expansion reservoir and radiator cap were located closer to the right front corner of the engine compartment. The fire patterns indicated an origin away from the engine compartment and were not consistent with engine coolant ignition.
- The lack of vehicle damage (i.e. frontal collision, bottoming out on a ditch) did not support a sudden rupture of fuel lines or other fluids that may interact with hot surfaces.
- Although accelerant detection canines detected an accelerant, that finding is not surprising in a vehicle fire scene, given all the different fluids involved. Subsequent laboratory analysis did not reveal any accelerants.
- No recalls for the vehicle were reported.
Since the vehicle was found in neutral gear, it is unknown whether the vehicle’s ignition was on at the time of the fire (or just prior to). While the fire cause was classified as undetermined, it did not appear to be a post-collision fire.
Biomechanical Analysis of Injuries
The victim showed injuries from extensive burns and trauma. The major traumatic injury was a skull fracture. Two lacerations and a scalp contusion were found on the forehead, and the victim also experienced bilateral subdural hemorrhages and epidural hemorrhages inside the skull. Burn injuries were observed on the back of the head, torso, and extremities.
One theory proposed was that the injuries were the result of a high-speed car crash without a seatbelt. However, a high-speed frontal crash would likely have ejected the victim from the car or at a minimum, propelled the victim violently forward into the interior of the car. Instead, the victim was found lying in the front seat. The steering wheel did not show mechanical deformation (Figure 4) and the victim did not show evidence of accompanying rib or extremity injuries.
Figure 4: The steering wheel for the vehicle
An alternate theory suggested that the victim’s head injuries resulted from some type of direct blunt impact assault.
- The split lacerations to the forehead were consistent with direct blows by a rigid blunt object like an aluminum bat or steel pipe.
- The force needed to cause the skull fracture most likely came from a blunt object. The skull fracture was likely the result of two blows: a first blow initiating the fracture, and a second blow causing the fracture to spread.
- The brain injury would have required a severe blow to the head.
- The lack of other injuries (rib fractures, other injuries to the face or extremities) was consistent with an assault to the head, which would instantly incapacitate the victim.
Overall, the physical evidence and injuries sustained by the victim pointed directly toward an assault rather than a frontal car crash.
In the end, the forensic analysis revealed that the vehicle most likely did not leave the road randomly. Given the lack of collision damage to the vehicle, and the various obstacles along its path, it is unlikely it would have traveled such a long distance (after the collision or maneuver that caused it to go off the road) on its own. Similarly, the fire damage to the vehicle was not consistent with a natural or accidental fire. While the cause was undetermined, there were indications of possible incendiary factors (irregular fire patterns, unexplained explosion, etc.). Finally, the victim’s injuries were consistent with blunt force trauma from a foreign object rather than a vehicle collision or fire.
While proving who committed this act was not in the scope of our work, the evidence and analysis from the crash reconstruction, fire origin and cause investigation, and biomechanical analysis suggested that the incident was the result of an intentional act. Forensic engineering analysis can often prove critical to understanding the evidence in cases like these, and often requires expertise from different engineering disciplines for case resolution.