COLLEGE STATION, Texas President John F. Kennedy's assasination silenced the nation, but the investigation into his death sparked plenty of conversations and controversy.
One of the big questions was whether Lee Harvey Oswald acted alone.
In 1976, the House Select Committee on Assassinations heard evidence from University of California-Irvine Chemist, Dr. Vincent P. Guinn, who said he could tell how many bullets were fired on the presidential motorcade, thus ruling out the second assassin theory.
The committee believed what they heard, and since then, Dr. Guinn's Comparative Bullet Lead Analysis method has been used in hundreds of cases and lead to numerous convictions. Including Bryan resident James Otto Earhart who was executed in 1999 for the murder of a nine-year-old girl.
"Unfortunately, through flawed science, he misled the committee," said Texas A&M professor of statistics Cliff Spiegelman.
Spiegelman, along with a team of experts put Dr. Guinn's theory to the test years later. What they found changed the way prosecutors look at evidence.
"The claim by Dr. Guinn was that the bullets used to kill president Kennedy and wound Governor Connally were chemically unique, even though they were manufactured in batches," said Spiegelman.
If the chemical makeup of each bullet was unique, Dr. Guinn claimed he could count the number of bullets by measuring the chemicals from each fragment. Dr. Spiegelman and his team disagreed.
"We got a hold of some antique bullets from the lots that were supposedly used in the assassination, and we showed that they were not chemically unique," said Spiegelman. "In fact, we found one that matched an assassination bullet."
Spiegelman's team concluded that since bullets, like pre-packaged cakes, are made in batches, the ingredients that make them up are the same.
"Twinkies aren't unique, cakes aren't unique, and bullets aren't custom made. Except for the Lone Ranger who makes silver bullets," said Spiegelman.
Since 2005, law enforcement no longer accepts CBLA as evidence, and Spiegelman has been asked to speak about the team's findings on dozens of occasions.
"Even when there are enormous resources put into forensic science, it can be flawed," said Spiegelman.
Spiegelman was also selected to be one of the nine-member Technical Advisory Group, for the Houston Crime Lab. A panel that will advise the independent city-chartered organization that took over the Houston Police Department forensic division. The advisory body will provide input on best practices in forensic science and lab operations.