By Eric Blandupdated 1 hour, 19 minutes ago
A team of experts assembled by the Discovery Channel has recreated the assassination of John Fitzgerald Kennedy. Using modern blood spatter analysis, new artificial human body surrogates, and 3-D computer simulations, the team determined that the sixth floor of the Texas School Book Depository was the most likely origin of the shot that killed the 35th president of the United States.
"The question we were trying to answer is, given the spatter evidence in a vehicle, and knowing an individual was sitting at a particular location, is there something we could use to determine where the shot originated?" said Steve Schliebe, a blood spatter and trace evidence specialist with the Los Angeles Sheriff's Department, who was part of the special investigation.
While blood spatter analysis existed in the 1960s, modern innovations have greatly improved its accuracy and the amount of information that can be gleaned from drops of blood.
"A lot of this is still fairly new, from the last 10 to 15 years," said Bevel. "Before that we thought we knew what was going on, but because of innovations like high-speed photography we have a much better appreciation of what is actually taking place."
On Nov. 22, 1963, at 12:30 p.m. Central time, President John F. Kennedy was shot twice while traveling in his limousine through Dallas, Texas. The first shot entered Kennedy's back and exited out of his throat. A second shot entered the left side of Kennedy's head and exited out the right side, spraying a nearby officer agent and the car's interior with bodily material. Kennedy was pronounced dead at 1:00 p.m. at Parkland Hosptial.
Lee Harvey Oswald was arrested an hour and twenty minutes after the shooting. Widely believed to have fired the shots that killed Kennedy, Oswald was shot and killed by Jack Ruby before he could be brought to trial.
Conspiracy theories abound on the number of shots fired, the number of shooters, and the location and identity of the shooter(s). The goal of Discovery Channel's Nov. 16th special, "JFK: Inside the Target Car," was to explore the theories and determine where the shots most likely came from using modern forensic science.
A mock-up of the Dallas, Texas crime scene was set up, including the depository, the "grassy knoll," and other nearby landmarks. Artificial surrogates of Kennedy were placed in a car. Sharpshooters then shot the surrogates from the model depository, the grassy knoll, and four other plausible locations.
Schliebe, along with Tom Bevel, an independent expert forensic investigator, were brought in to examine the simulated crime scene. Both scientists had no idea what the experiment was for or that it was a reenactment of the JFK assassination.
The two experts found a simulated gunshot would to the head that closely matched the wound Kennedy suffered. Most of the simulated body material had spattered forward into the car, consistent with a shot that entered the back of the head and exited toward the front. There was some back-spatter — material that flew back in the opposite direction of the bullet's trajectory — but not much.
The general lack of back spatter and the preponderance of spatter in another direction are two of the clues, among others, that the investigators used to pinpoint the origin of the shots.
"After Tom and I looked at the scene, we pointed up and back away from the vehicle," said Schliebe. "Apparently that lined up perfectly with where the sharpshooter had hit the model head."
Along with advances in blood spatter analysis, another advantage modern forensic experts have is simulated body parts.
The team used some of the most advanced artificial human heads in the world for the ballistic tests. Made from a proprietary mixture by Australia-based Adelaide T&E Systems, the heads have three different materials which simulate the brain, skull and external soft tissue (skin) — that together respond to the trauma the same way a human head would.
The simulated brain material was made from a pig-skin-derived gelatin, dyed green. The skull surrogate is made from a special vinyl ester resin filled with calcium and proprietary fibers. The artificial skin uses a polyurethane and plasticizers to mimic human skin's physical properties. The head was even custom-fitted, based on Kennedy's hat size.
"The heads they used were quite interesting," said Bevel. "They were considerably more sophisticated than anything I've seen before."
In addition to the physical environment, a virtual environment was also set up. A team from Los Angeles-based Creative Differences went to the original Dallas crime scene and took precise measurements of all the angles, distances, wind speed and directions, etc., in the area to create a 3-D model of the crime scene.
To animate it, the team looked at a video of the assassination filmed by Abraham Zapruder. The Zapruder film, as it's called, is generally believed to be the most complete video of the shooting because of its clear view of the motorcade and the height it was shot from.
Only two of the 486 Zapruder frames actually show Kennedy being shot. Computer graphics expert Doug Martin highlighted the red parts of the frames and the blood resulting from the wound, and plotted them onto the computer simulation to see where the fatal shot came from.
"We might never know if Oswald pulled the trigger, but when you look at the wind pattern, the spread of the debris, the angles and distances involved, it's consistent with a shot from the sixth floor depository," said Martin.
This kind of computer analysis has only been available for about five years, says Martin. He expects criminologists will continue to make use of 3-D crime scene simulations to help reconstruct events and gather evidence a 2-D picture alone can't reveal.
"I think this is the wave of the future," said Martin. "If we had this technology back in the '60s, I think it would have put a lot of the conspiracy theories to rest."
© 2008 Discovery Channel
