WI DUI: What is Certainty? What is Uncertainty?

In drunk driving cases, breath and blood test results are reported as a number. We are all familiar with the number: .08. This number is deceptive and unfair, because it fails to state a level of certainty. We have a number, but we do not know how accurate, precise or reliable it is.

In its report on the state of forensic science in the United States, the National Academy of Sciences recommended that all forensic measurements, such as blood test results, be reported with an “uncertainty budget.” That is, the number should be reported as, for example: .08, plus or minus .005 to a 95% degree of certainty.

In this way, a judge or jury will, at least, have a basis to decide how much weight to give the number. Since the NAS report, skilled and knowledgeable DUI defense lawyers are demanding that the test results be reported with an uncertainty budget or that they not be allowed into evidence.

We are just at the beginning of this fight. And the forces that protect slipshod procedures in DUI prosecutions will fight back. In their world, it does not matter if the science is fair, accurate, precise or reliable. What matters to them are that people accused of DUI are convicted as cheaply, quickly and easily as possible.

My good friends and colleagues Ted Vosk, of Seattle, Washington, and Justin McShane, of Harrisburg, Pennsylvania, are the national leaders on this issue. At the Law Offices of Andrew Mishlove, we are following this very closely. We are studying the complex science of uncertainty budgets and maintaining communication with other lawyers across America who are preparing for this battle. We will be at the front lines.

The Wisconsin Legislature recently adopted the more stringent “Daubert” standard for the admission of scientific evidence in Wisconsin courts. It is unclear how this new standard will affect breath and blood test results and how the emerging concept of “uncertainty budgets” will fit into our new scheme of scientific evidence.