There's an interesting case pending before the Connecticut Supreme Court. The Court states the issues as follows:
[T]he defendant sought to introduce expert testimony regarding, among other things, the following identification concepts:
- (1) that witnesses who experience heightened levels of stress during a crime tend to make inaccurate identifications;
- (2) that under the "weapons focus effect," witnesses tend to focus on a perpetrator's weapon as opposed to the perpetrator's facial features;
- (3) that there is a weak correlation between a witness's confidence and the accuracy of an identification;
- (4) that pursuant to the "disguise effect," a perpetrator's use of a disguise makes an accurate identification more difficult; and
- (5) that when multiple witnesses discuss the crime with each other, the different versions become melded in such a way that the witnesses can no longer be certain of what they actually saw.
The trial court prohibited the defendant's expert from presenting testimony regarding these concepts, concluding that they were matters of common sense.
How did the trial court conclude that it was common sense? Did the court ask the jurors in voir dire about eyewitness identification bias and decision making?
The actual, empirical, real research shows that people consider eyewitness identification to be highly reliable. There are, however, some common sense exceptions.
People consider external factors in determining whether an eyewitness identification is reliable. If it can be shown that it was dark outside, jurors are less likely to believe an eyewitness. If it was raining, or the witnesses wasn't wearing her glasses, or if the witness is a geriatric: Jurors view eyewitness identification suspiciously. Those are matters of common sense.
The really interesting stuff, however, is not. It's the stuff that is in the inside of an eyewitness's mind that jurors don't understand. Let's look at one example. Please bear witness to this video:
http://www.youtube.com/watch?v=nkn3wRyb9Bk Most people clearly miss something huge. The concept is known as inattentional blindness or change blindness.
We can only see what we are paying attention to. When we are paying attention to one thing, we miss something obvious about the rest of the scene. Here is another example of change blindness:
Now, how does that related to eyewitness identification? If I point a guy at someone's face, what will you focus on? It won't be my eyes, ears, or nose. It'll be the gun. That is scientific fact. How then could you reliably describe my face?
Now, maybe it's still possible to pay attention to the gun and my face. Still, most people are not able to. Here is an abstract from one (of many dozens) of studies:
Three experiments investigated the role of 'change blindness' in mistaken eyewitness identifications of innocent bystanders to a simulated crime. Two innocent people appeared briefly in a filmed scene in a supermarket. The 'continuous innocent' (CI) walked down the liquor aisle and passed behind a stack of boxes, where upon the perpetrator emerged and stole a bottle of liquor, thereby resulting in an action sequence promoting the illusion of continuity between perpetrator and innocent. The 'discontinuous innocent' (DI) was shown immediately afterward in the produce aisle. Results revealed that: (1) more than half of participants failed to notice the change between the CI and the perpetrator, (2) among those who failed to notice the change, more misidentified the 'CI' than the 'DI', a pattern that did not hold for those who did notice the change. Participants were less likely to notice the change when they were distracted while watching the video
Did most of you - judges, lawyers, law professors, and smart people in other professors - know about change blindness? If your answer is yes: Did you know about it before you studied the issue? In other words, was it a matter of "common sense" to you?
Of course not. Change blindness is part of a body of literature on cognitive bias that is only a a few decades old. Although some of these concepts are being popularized by books like Predictably Irrational, the knowledge hasn't trickled down to the Main Street juror.
Why shouldn't lawyers be allowed to educate jurors about the faults of eyewitness identification? Perhaps there are good reasons - although I haven't heard any. That inattention blindness is a matter of common sense, however, is not such a reason.
