Ithaca DWI Lawyer: What is the DWI Defense of Extrapolation?

From Dreamstime, Last Call for Alcohol

With every DWI case that has a blood or breath test, aka THE chemical test there will be a gap of time between police contact and the test. If there is an accident it takes time for the police to arrive at the scene and assess it. If there is a stop of a car for a traffic violation there is a process and procedure that is followed. All the police questions and the field sobriety testing, and the drive back to the station or trooper's barracks take TIME.

Time can always be your friend or your enemy. This is true in any case involving forensic police testing of a DWI or DWAI drugs body sample of breath or blood or urine. The clock is always ticking. Minutes and hours that drag by can affect your body's processing of toxins. And shots and chugging take so little time. As my daughter loves to tell me of all the new college drinking games like flip cup and circle of fire. So what's this thing called "Extrapolation" and how does it relate to being a DWI defense?

Extrapolation is a Fancy Word for Looking Backwards or Forwards from Known Facts 

You can in fact try to estimate or predict where something was by where it currently is. Just as you can in fact try to estimate or predict where something will be by where it is.

You Start with a Known (Your DWI BAC) at a Specific Point in Time

Both methods (forward or backwards) look at a current point or space in time, In other words if your BAC (blood alcohol concentration) was tested at .11 at 10:00pm, what was it at 8:00pm? Well if your blood alcohol level was still rising at 8:00pm then it was lower than .11 BAC. But if your blood alcohol level was falling then potentially it was higher than .11 BAC at 8:00pm.

The One Primary Weakness with All New York Police Blood and Breath Testing is ONE Test 

The rise and fall of alcohol on a curve can NOT be plotted by merely looking at one test at one point in time. In New York state the police ONLY use ONE test at one time to figure out your BAC at time of driving (operation) for DWI. Now in theory your BAC could have been on the rise or could have been on the fall at the time of testing.

You are a Unique Individual and Alcohol Absorption and Elimination is a Science 

We would need a lot more information about you, such as what you drank, when you started to drink, when you stopped drinking, what you ate, when you ate, etc. to make any kind of reasonable estimate of whether your BAC was on the rise or fall at the time of breath or blood chemical testing.

The Extrapolation Defense Argues that Your BAC at Driving was Lower than at Time of Testing

The greatness of the DWI extrapolation defense lies in that an argument could be made in either direction since the police ONLY do ONE test ONE time. Remember that ONE sample at ONE point in time doesn't tell us much except what your BAC level was at the specific moment. I can argue to a jury that you were still absorbing alcohol at the time of driving. If you were In the absorption phase that means that your drinks were closer in time to the driving.

The Last Gulp is the Crux of the DWI Extrapolation Defense

The last gulp defense is the extrapolation defense in a Nutshell. You took those last shots, chugged those last drinks and then drove NOT feeling the effects and certainly NOT intoxicated. The police pulled you over and arrested you and processed YOU and then the alcohol rose up in your blood stream to illegal levels. Then you were tested. Your BAC at time of testing was NOT accurate of your BAC at time of driving.