If it were true that fingerprint errors had different superficial attributes
from correct conclusions, detecting errors would not be difficult. We could
simply devise ways of detecting incompetent examiners, bad days, highpressure
laboratories, and so on. But the insidious thing about fingerprint
attributions is that they look just like correct attributions, until we identify
them as misattributions.
In short, retrospective explanations of fingerprint misattributions will
not help us learn to identify them prospectively. This is the intended
meaning of my epigraph—not, as the reader may have initially assumed, to
liken latent print examiners to charlatans. The epigraph highlights, with
absurd precision, the obvious point that the insurance scam only works
because the mark cannot prospectively tell the difference between an honest
insurance salesman and an imposter. The same is true of a fingerprint
identification. The criminal justice system has no way of prospectively
distinguishing between correct latent print attributions and misattributions.
But, more importantly, it is true of the latent print examiner as well. A
falsely matching known print (an imposter) presumably looks much the
same as a truly matching one. What this leaves us with is an empirical
question about latent print examiners’ ability to detect imposters.363 All the
rest of it—good intentions, the fact that there is only one finger that left the
print—is beside the point. Latent print examiners are not the phony
insurance salesmen of my epigraph; they are the victims, the unwitting
consumers.