By Dr. Ken Broda-Bahm:
Litigators tend to implicitly believe that evidence can overcome attitudes and bias. Yes, it may be an uphill battle against a judge or juror's hardened beliefs, but once they pay attention to the evidence, we will be able to change their minds, right? Even as we strike some, the faith that we can convert most is a cornerstone of the adversary system. But that faith depends on our target's use of analytical ability. What if analytical ability itself isn't reliable, but is instead beholden to attitudes and biases? What if the very faculty that would permit us to change our minds actually dials itself down when confronted with information that threatens current beliefs?
It is one of the more depressing recent findings on human cognition, but it turns out to be correct: We become less smart when evaluating attitude-inconsistent information. A recent study coming out of Yale Cultural Cognition Project (Kahan et al., 2013) looked at the ways our ideological beliefs interact with our numeracy: That means being "number-smart" or, more technically, "a disposition to engage quantitative information in a reflective and systematic way and use it to support valid inferences." That tendency, which goes beyond math and also reflects a disposition to engage in effortful and deliberative thinking, obviously matters a great deal in a legal context. The study shows that being high in numeracy does not reduce the tendency to interpret complex data along the lines of preexisting beliefs, instead it increased that tendency. In other words, "more numerate subjects would use their quantitative reasoning capacity selectively to confirm their interpretation of the data to the result most consistent with their political outlook." That finding carries some profound implications for litigators and this post will take a look at a few.