I have often enjoy re-telling the old joke about how there are three kinds of lies: 1) Lies, 2) Damn Lies, and 3) Statistics. Many of my federal criminal cases here in Atlanta and elsewhere involve one or more of these three types of “incorrect” information. Some government witnesses tell little lies, while others tell big whoppers that are flat-out lies designed to help the liar and hurt my client. On some other day I will pontificate about how the system of rewarding “cooperating witnesses” is a perversion of our justice system that leads to some its greatest failures. But today, I want to talk about how statistics and their analysis and manipulation can sometimes be the greatest lie of all.
Now remember, most lawyers are not “numbers people.” That’s the reason we went to law school, because some teacher or school just flat-out insisted that we needed to learn calculus. For the most part, attorneys are not at their strongest when dealing with mathematic or scientific issues. While most good trial lawyers are bright and can quickly pick up new concepts, this is not our main area of expertise.
So, we have a system where most of the main participants are not all that great with numbers or science, and then we have cases that are chock full of both types of information. Here is what usually happens. A prosecutor hears about a new type of evidence, such as DNA analysis and comparisons to see if the person on trial had some connection with the victim or crime scene. It’s only been 30 years since this evidence was first accepted into court, and in the early years virtually all prosecutors and defense lawyers simply deferred to whatever the “experts” claimed. Then as time progressed, more and more lawyers got comfortable with the basic science behind DNA analysis, and began poking holes in the claims, leading to the far too many cases where DNA analysis has actually exonerated previously convicted Defendants.