Getting the Real Skinny on Government Press Releases
February 10, 2005
by Joseph P. Tartaro
Executive Editor
Did you hear the one about the people challenging the FBI Laboratory’s comparative bullet lead analysis (CBLA) system?
Probably not! That’s another one of those stories that the general media likes to bury—like the recent report by the National Academy of Sciences (NAS) which said their researchers could find no empirical evidence that gun control had reduced crime anywhere; or the report from the Maryland State Police that called the state’s ballistic imaging system for new handguns a failure.
Even when the media do print or broadcast news about such studies that run counter to their social agenda, the information is slanted or abbreviated so the public doesn’t get the full or true story. It’s the same way when they report on any piece of federal or state legislation; they give you only a title of the bill or a single aspect of it, usually leaving out critical details.
In the case of the recently related NAS study (See Gun Week, Feb. 1 article by John Lott) which was over 300 pages long, they reported only that the study saw a need for better research into the issue and more study, taking some of their slant from the Brady Campaign to make it sound like Congress was preventing the collection of such data. However, the data studied included information drawn from FBI Uniform Crime Reports and other government documents, which the NAS team reviewed but the media ignored.
Other Sources
Fortunately, there are many other information sources available to the public these days, although not the kind you would find on your TV set, or have delivered to your door by the paper kid. For this column, most of the citations came from The Champion, a monthly magazine of the National Association of Criminal Defense Lawyers, and corroborated by Science News Online (www.sciencenews.org).
This column deals with a more esoteric subject than the NAS gun law survey or the Maryland ballistic imaging issue. However, it is one that should be of interest to shooters and gunowners, because it involves questionable testimony that could be given against you or a neighbor in a criminal trial.
Our system of justice is predicated on the bedrock concept that a person accused of a crime is to be considered innocent until proven guilty, although the media and some prosecutors often forget that. At trial, a guilty verdict would require evidence that would prove guilt beyond a reasonable doubt that the defendant committed the crime in question. Often, such evidence is of a circumstantial nature.
For example in this instance, if a bullet or its fragments recovered at the scene of a crime is subjected to bullet lead analysis, and investigators find a box of ammunition in your possession with a similar composition, an expert witness might testify that the crime scene bullet came from your box of ammo. That was the way prosecutors linked a suspect to a particular crime when no other evidence or witnesses were available. And juries have convicted on the basis of such evidence.
Second Thoughts
Sounds weird, but it has happened. That’s why a number of technical experts, lawyers and scholars have had second thoughts about the current process of comparative bullet lead analysis (CBLA) as practiced in the FBI Laboratory.
Scientific and legal questions about the system have received enough currency that the FBI Laboratories in 2002 asked the National Research Council (NRC) of the NAS to review the entire laboratory system and the way FBI lab technicians testify at trials.
One of the key critics of the FBI CBLA approach is William A. Tobin, who retired in 1998 as a supervisory special agent after 27 years of service with the FBI. Twenty-four of his FBI years were spent as a forensic metallurgist at the FBI Laboratory, 12 as de facto chief forensic metallurgist.
In a way, one might ally Tobin with other important FBI whistle-blowers who have challenged other aspects of FBI lab work or testimony.
In February 2004, the Department of Justice released a bulletin summarizing the findings the NRC on bullet lead analysis, leaving the impression that the NRC approved of the FBI protocols and concluded by noting, “Recommendations by the NRC included suggestions to improve the statistical analysis, quality control procedures, as well as expert testimony.” That’s the short form of the report, and was probably all one found in most media outlets when it was announced last year.
But that’s not the whole story.
In an article in The Champion (July 2004), Tobin goes into much more detail regarding the problems he and others have with CBLA as currently handled by the FBI Laboratory and provides a more detailed and instructive report of the NRC’s findings.
Tobin’s extensive article, “Comparative Bullet Lead Analysis: A Case Study in Flawed Forensics,” focuses on the failings in the FBI’s use of during the investigative process and later at trials.
The CBLA system was first developed in the 1960s and has been used in cases where the suspect’s firearm was never recovered or entered as evidence. It is a scientifically accepted system in which chemical analysis measures seven trace elements present in lead alloys used in bullet castings. The seven elements present in the lead which are measured include: arsenic; antimony; tin; copper; bismuth; silver and cadmium. The comparative amounts of these trace elements are measured to link a particular bullet or fragment to a given lot of lead.
Although there is disagreement in some aspects of the CBLA process, everyone agrees that the CBLA technique has been used in approximately 2,500 cases since the 1980s, and in about 20% of those cases, bullet lead compositional analysis was presented as circumstantial evidence in court.
In some of those cases, the FBI’s expert witnesses have gone so far as to testify at trial that their analysis of a bullet or fragments collected at a crime scene actually came from a particular box of ammunition possessed by the defendant.
Tobin’s article in The Champion, which has also been cited in an article in Science News Digest challenges many aspects of the CBLA system used by the FBI laboratories and especially such positive testimony by an expert witness. Tobin claims that such a positive link to a particular box of ammo is impossible. At best, he says, CBLA might be successfully linked to a lot of lead originally shipped by a smelter to a bullet manufacturer.
Tobin says there are too many variables and he explains the details of commercial lead recovery, usually from batteries, and sales to bullet manufacturers, as well as the complexities of the bullet making process itself, and the distribution system for commercial ammunition. Finally, Tobin reviews the standard by which any expert witness can testify in court.
In his article, Tobin lists all of the findings and recommendations made by the NRC report. They are much more extensive than the Department of Justice bulletin on the subject implies, perhaps that’s why nobody in the general media conveyed that information to the American public.
There are nine NRC findings related to the analytical methodology of the FBI Laboratory. There are eight related to the statistics used for comparison purposes. There are five dealing with the significance of the manufacturing process in the interpretation of evidence, and there are seven findings relating to the legal interpretation of the data.
In the main, the NRC report agrees with the objections of Tobin and other critics of the FBI Laboratory’s approach. It concluded that because certain information is not available to the laboratory, and thus it is not possible to obtain accurate and easily understood probability estimates, an expert should not testify as to the probability that a crime scene bullet came from a particular defendant.
All of which illustrates that reporting simply from government press releases may not be in the best public interest.
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