BAC levels close to the legal limit in Michigan DUI Cases - What can be done to beat a drunk driving case

When a client contacts me with a drunk driving case, it's important to discuss any chemical tests. The two most common are the Datamaster or a blood draw; once we know the number, we put together a timetable of alcohol consumption to see if the BAC level at the time of the exam could be accurate, or if there is a major issue with it.

If the numbers make sense, we're still going to question the result, and make the prosecutor provide evidence beyond a reasonable doubt to its accuracy, but it may not be our #1 focus, we can make other parts of the case our true leverage point. 

If my client says they drank 8 beers in 3 hours, and the BAC level is 0.12 or so, that makes sense. Each beer is about 0.02, which would be roughly 0.16 of alcohol, but we have a few hours of consumption to burn some of the alcohol off, and lower the number.  If the same client says they had 2 beers, and we have a BAC level of 0.20, either the client is not telling me the truth, or there is a major flaw in the test result.  

If a client has a BAC number close to the legal limit, which I consider 0.08 to 0.12, the timing of consumption is very important.  If a client has 4 beers in 2 hours, but 2 of those beers were consumed right before leaving the bar, and the client is pulled over soon after, those beers are unlikely to have "registered" in my client's body.  Yes, those beers show up an hour later during a Datamaster or blood draw, but the legal standard is the BAC level while driving the car.  

The Michigan jury instructions will instruct a judge or jury that they may consider the chemical test result to be the same as when the person was driving, but applying common sense, that is simply a lazy jury instruction put in place to make the jury's job easier to convict.  Imagine if the prosecutor had to show the BAC number when actually driving?

You'd need to have 1000's of Datamaster machines in the back of vehicles and hustle the driver into taking a test, skipping key procedures like the 15 minute rule etc.  

There's many other factors that go into the accuracy of the BAC reading, but I find the timing and amount of consumption to be the easiest for a jury or judge to understand at trial.  Attacking the blood draw or testing or the Datamaster machine is certainly viable, but it's more difficult to get a jury to understand how a machine did not work vs simply applying common sense. 

If you or someone you care about has a DUI case in Michigan with a BAC number near the legal limit, they have a viable built in defense, which can be a winner at trial if presented in the right way. 

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