Here is another great post by James Warner Wallace
Following Dateline’s airing of our latest cold-case (“The Wire”), I received a number of concerned emails from viewers who felt there simply wasn’t enough evidence to be certain Douglas Bradford killed Lynne Knight. I think I can see their point. Dateline has done an excellent job chronicling four of our investigations, but our cases are nearly impossible to adequately represent in the limited time Dateline has to tell the stories. Why? Because our cases are complex, layered, cumulative, circumstantial cases. While I’ve written often about the nature of circumstantial evidence, one of the most important evidential concepts related to our cold-cases is the role of cumulative arguments. When a large quantity of evidence points to the same suspect, the cumulative impact of this evidence can be powerful. Many of the individual facts and evidences may seem unimportant or trivial on their own, but when assembled as a set, their collective weight becomes unbearable.
All my cold-cases are built in this way. We assemble dozens of facts, details, inferential statements and evidences and show the jury how the collective set of evidence implicates our suspect. I’ve often referred to this process sarcastically as “Death by a Thousand Paper Cuts”. Defense attorneys typically respond to cumulative cases by focusing on those few pieces of evidence they believe to be the most damaging for their client. They then try to show how any number of other, unrelated causes might also explain these specific items of evidence. They want jurors to focus on the individual pieces rather than the collective set. In essence, they hope jurors will see the “trees” rather than the “forest” (and hopefully only a few of the trees, at that!) In the end, defense attorneys explain the evidences by way of many unrelated causes rather than by the simpler explanation: their client is the one causal factor who can account for all the evidence in the case. In many ways, it’s an “Ockham’s Razor” exercise. When one causal factor explains all the evidence in the case, that cause is the simplest (and most reasonable) explanation.