CSI | PROBABLE CAUSE

The use of forensics in television dramas has created a legal phenomenon known as the “CSI effect.” Jurors today often view forensics as gospel based on what they see on their favorite shows. The August issue of Popular Mechanics magazine attempts to dispel some myths in a cover story entitled, “The Truth About Forensics”.

In real life, many forensic labs are understaffed and have a huge backlog of requests for services. Some state and city forensic departments have mishandled evidence, and since no advanced degree is required for a career in forensics, personnel with minimal credentials staff many of the labs around the country.

But a more serious issue emerged last February when the National Academy of Sciences issued a report noting that, “apart from DNA, there is not a single forensic discipline that has been proven with a high degree of certainty to be able to match a piece of evidence to a suspect.”

While DNA is considered the gold standard of identification, a debate is growing between defense attorneys and forensic experts concerning the scientific validity of fingerprints, footprints, tire tracks, bite marks, blood-splatter patterns, ballistics, hair, fiber, and handwriting analysis. Evidence such as voiceprint analysis and lead analysis of bullets already has been completely discredited.

According to the article, despite the widespread belief in the accuracy of fingerprints, “no studies have proved definitively that fingerprints are unique, and it’s unclear if prints change over time or vary depending on the amount of pressure applied.” Studies quantifying the probability of error in ballistics matching also should be done. Currently, it’s impossible to say with certainty that the marks made on fired bullets are unique to an individual gun.

Alternately, paint analysis has a relatively strong scientific backing and can provide reliable results. While fiber analysis has a foundation in chemistry, more research is needed to determine the criteria for a match. The article points out that current methodology is only sufficient to conclude that fibers could have come from the same type of garment or carpet. Research has also shown that matching hairs using subjective analysis can be highly inaccurate.

Software to help quantify the certainty of fingerprint matches is currently being developed, as well as a database of microscopic tool marks to give statistical significance to the identification of burglars’ tools. But it appears that more forensic research needs to be done. As a writer of police procedurals, forensics often plays a role in the solution of my fictional crime stories. Since I want my novels to be as accurate and believable as possible, I’ll continue to follow the latest research. Hollywood should do the same.

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CSI, CSI Miami, and CSI New York are consistently three of the most watched shows on television. In a recent Nielsen ratings period, both CSI and CSI: Miami finished in the top ten. NCIS, The Mentalist and Criminal Minds also finished in the top ten. Clearly, viewers are fascinated with crime shows, particularly those dealing with forensic science and how it is used to conclusively solve crimes.

But last February, the National Academy of Sciences released a comprehensive report citing “serious problems” in the scientific evidence being presented every day in courtrooms around the country. The academy found “no forensic method has been rigorously shown able to consistently, and with a high degree of certainty, demonstrate a connection between evidence and a specific individual or source.”

And the Supreme Court recently ruled that crime lab reports may be introduced as evidence in court only if defense attorneys can cross-examine the persons who prepared them. The 5-4 decision involved a cocaine trafficking conviction that was based, in part, on evidence obtained from plastic bags found in a car in which the defendant was riding.

Defense attorneys wanted to interview the forensic analyst about how the evidence was collected and tested, but a Massachusetts court turned down their request. Later, the National Innocence Network argued that the testimony was vital because of errors in crime labs across the country.

I’ve written in the past about DNA evidence and how it has been used to free the wrongly convicted. But often DNA and other evidence such as hair, bite-mark comparisons, fingerprints, firearms, tool marks and shoe prints are used to convict individuals in real life, just as in those highly rated, fictional television crime shows.

Take the case of Philip Scott Cannon, a convicted murderer serving three life sentences in an Oregon prison for a 1998 triple homicide. A former Oregon State University researcher in the university’s Radiation Center testified that tests showed bullets found at the crime scene matched those found in Cannon’s garage. He told jurors there was only a 1 in 64 million chance of getting that match. Cannon was convicted primarily on bullet lead analysis. However, the FBI no longer uses bullet lead analysis and considers it unreliable. Cannon’s defense lawyers are challenging the accuracy of his conviction in a hearing scheduled for July 7^th.

It’s anyone’s guess as to how many cases or convictions have resulted from flawed forensic science. The Innocence Project reported that approximately 50 percent of the wrongful convictions overturned with DNA involved invalidated or improper forensic science.

It’s unlikely CSI will offer episodes in which their forensic scientists make mistakes and convict an innocent individual. But viewers who believe that CSI shows are gospel better think again. It’s apparent that the criminal justice system is just beginning to face the fact that many of those sitting in prison today, may have been convicted using discredited forensic science.