Sidestepping Proof

Lawrence Taylor at DUI Blog touched on an interesting way that state legislators have tried to get around proving that a person was actually driving while intoxicated. Most states require that the prosecutors engage in a process called retrograde extrapolation to prove that a breath, blood, or urine test taken some time after arrest (and obviously, after driving) has the requisite bearing on BAC while the person was driving. In California, Vehicle Code Section 23152(b) makes it a:

rebutable presumption that the person had 0.08 percent or more, by weight, of alcohol in his or her blood at the time of driving the vehicle if the person had 0.08 percent or more, by weight, of alcohol in his or her blood at the time of the performance of a chemical test within three hours after the driving.

This forces the defendant to prove that a sample taken 3 hours before he was observed driving is inaccurate, essentially flip-flopping the presumption of innocence. How? Well, the body could still be absorbing alcohol into the blood from the stomach and the person who blows a 0.09 at 12am could easily have been a 0.05 when pulled over at 9pm.

Under Mata v. State (46 S.W.3d 902 (Tex. Crim. App. 2001)), the State must prove that the defendant was actually intoxicated while driving, not while submitting a breath test. But it's not as if MADD isn't trying to destroy the presumption of innocence through legislation. Look for this bill to get re-submitted in the 2009 Legislative Session by another legislator who doesn't grasp one of the most vital cornerstones of our criminal justice system.