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To blow or not to blow part 3

So now you know a little bit more about how the magic box works, what do you need to know next? The important thing to know is that they can be highly unreliable. These magic boxes that sit on the police officers dusty old desk are not all they are cracked up to be. Unfortunately the boxes are powerful, they have the power to single handedly convict in the overwhelming majority of cases, then when you add on top of that the arresting officer’s 100% candid and non-biased statement of facts resulting from the arrest, things can get pretty gloomy.

Let’s take a look at a few ways these machines are not accurate or fair. As indicated in my prior post, the machine bases its calculation on a ratio of alcohol from blood to breath of 2100:1. That is 2100 units of alcohol in the blood for every single unit of alcohol in the breath. The machine bases its entire existence on this ratio but the problem is many people do not fall into this “average person” category. True “partition ratios” can run from as low as 900:1 to as high as 3500:1. If a driver’s ratio is different than what the magic box bases its formula on, then the driver gets an inaccurate number and quite possibly a faulty conviction. The machine uses the same ratio for all people, men, women, big or small; the smallest woman versus the biggest man, the machine says you are all the same. Hmmm.

I have represented petite woman who have sworn they only had 3 glasses of wine yet they blew a .12; I have represented males under 5 feet tall, I have represented folks with known lung disorders, folks with cancer, all the same results. Numbers high enough to convict because the machine says so, but in all likelihood the box was wrong. Naturally none of these folks went to jail, even when they were multiple offenders, but they still had to retain counsel to fight the darn box. They still had to go through a very uncomfortable and expensive process all because their individual partition ratio was different than what the machine says it should be.

Other than partition ratio, are there any other problems you should know about regarding the accuracy of the box? Why yes, funny you should ask. If you are a diabetic the machine can misread, if you are on a diet and have recently lost significant weight, the machine can misread, if there is radio interference in the police station (ie. cop radios), the machine can misread, if you recently placed anything in your mouth before blowing, the machine can misread, if you have a temperature at the time you blow due to menstruation, general illness or any cause, the machine will misread high.

Studies have shown and articles have been written regarding the temperature of the sample. The core body temperature is generally 98.6 degrees F. However, in the article Body Temperature and the Breathalyzer Boobytrap, 721 Michigan Bar Journal (Sept 1982) it discusses the fact that for every 1 degree higher than core temperature, the breath sample will register 7% higher secondary to Henry’s law of gases.

This list does not even begin to exhaust the possibilities of error regarding this box. Even Maryland law recognizes that the machine has a .01 margin of error before even getting into the aforementioned matters. There are other issues innate to the machine which can cause false high readings. Interestingly, most police officers/machine operators themselves are unfamiliar with the various short comings of the machine. Ask an breath test operator about the .05 mask which is built into the machine which allows the machine to operate on a blank air sample even though it registers up to .005, he won’t even know what you are talking about. However, the manufacturer of the machine does know and has discussed this in prior court testimony. The result, when you blow, the sample can read .005 higher than whatever your true number is without even considering any of the foregoing matters.

Oh yes, there is one other minor matter that has a very significant impact on the accuracy of your number which I will discuss in the next post.

Bruce Robinson Maryland DWI Defense Attorney www.mddwi.com