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Well, that made things a lot easier in California. Again, the conviction rate continued to go up. It became more and more difficult to defend people accused. I did not say "guilty". Accused of drunk driving. Well, but there’s still lots of defenses left, because, as I will I hope I will have time to get into, this machine is, to say the least, unreliable. But one of the problems is called retrograde extrapolation. And I alluded to it earlier. And that is, well it’s all well and good, he was a .11 at the time that he breathed into the machine at the police station. But it’s not against the law to be over a .08 in a police station. It’s against the law to drive a car over .08. What was it at the time he was driving?
Well, that caused prosecutors a lot of problems. And so most states, almost all states, passed a new law with the assistance of the Mothers Against Drunk Driving. And that law said, "Any test within three hours that results in a blood-alcohol reading, it shall be presumed that it was the same at the time of driving." Even though we know absolutely, as a matter of science, fact, that that is not true.
Well, that again raised the conviction rate, except it was a rebuttable presumption. In other words, you could introduce evidence that that simply wasn’t true. And so now, to make a depressingly long story short, some states are beginning to pass laws saying that the crime is having over .08 at the time you breath into the machine. And they don’t care what you were when you were driving the car. Notice how we’ve gotten further and further and further away from the evil we were trying to cure. And that is: "Were you impaired by alcohol when you were driving your car?"
Okay. Let’s take a look at this machine. The vast majority—in most states there is no urine and if there is blood, you’re usually not going to have access to it. In the vast majority of cases, because it’s cheap, easy and fast, you’re going to be breathing into one of these machines. Let me just give you a real quick rundown on theory and the book I wrote on DUIs is about 1200 pages long, of which about 400 pages are just on the technology of breath machines, so this is going to be very cursory. But, I think, for purposes of illustrating some of the problems, it will help.
Basically just taking, as I said, the alveolar air, injecting it through a tube into a sample chamber and capturing it in that chamber. It’s a little tube. Nickel-plated in most of the machines. And, by the way, there are a lot of different manufacturers around of these different machines, different types, but we’ll get into that in a moment. These machines rust. The sample chamber rusts, it absorbs alcohol from previous subjects and so on. But let’s just say for purposes of theory it captures a sample, a given volume of lung air, alveolar air. At one end it has a projector that projects infrared energy, infrared light, a beam through the chamber. Through your breath sitting in that chamber. Now, at the other end of the chamber is a receptor and it measures how much of this infrared energy gets through.
Now the theory of infrared spectroscopy, as applied to DUI cases, is that there is a part of a compound called the methyl group and that any compound containing the methyl group, will absorb the energy from this lightwave which is 3.61 microns. And that one of those compounds is ethanol, ethyl alcohol. Ethyl alcohol contains the methyl group as part of its molecular structure. It is resonant with this particular frequency of lightwave. So the more ethyl alcohol in the sample chamber, the more energy is going to be absorbed, the less will get through to the receptor, the higher the blood-alcohol reading will go. Actually fairly simple. Except, again, it is absorbed not by ethyl alcohol, but by the methyl group in any compound. In other words, it is a stupid machine. It does not differentiate between ethyl alcohol and any other compound. It is what we call "non-specific" for ethanol. Any compound on your breath that contains the methyl group will be detected as alcohol and reported as alcohol. If you happen to have 32 different compounds containing the methyl group on your breath, it not only will report them all as alcohol, it is cumulative. It will add all of those, including any ethyl alcohol and then report it as ethanol.
So, do any of these methyl groups exist in the human breath? There are a number of scientific studies—one of which indicates that there are 102 different compounds found on the human breath that contain the methyl group. So what you are getting is not alcohol. What you are getting is some unknown cumulative reading of any of these compounds on your breath. If you had been painting a house yesterday, today you would be registering alcohol. If you had been using solvents, or thinners or glue or anything like this. If you had pumped gasoline into your car and inhaled any of the fumes, hours, even days later, you will be breathing out vapors containing compounds with the methyl group in it.
Now the second major problem I’ve already mentioned or alluded to and that is the partition ratio. It is becoming less of a problem as the legal system chooses to pass laws or make rulings outlawing, essentially, science.
A third and this is just the last example I will give you, is called the mouth alcohol phenomenon. The machine assumes that the alcohol, or whatever it is measuring comes from your breath and that’s why it's multiplying by 2100. Obviously, if it is getting alcohol directly from your stomach or your throat or your mouth, it’s going to fool the machine and the results are going to go extremely high. It would take a minuscule amount of alcohol in your mouth, throat or stomach to fool the machine and go pretty high reading. This is called the trapped alcohol or mouth alcohol problem. So, if for example, you burp or belch and any gases from your stomach, or you have reflux condition, or a hiatal hernia and any of those gases or liquids come up, it will stay there for about 15 to 20 minutes before saliva dissipates it. It will be breathed into the machine, the machine will go an unknown amount high. It does not mean you’re under the influence. It does not mean you’re an .08. It’s simply that you had alcohol in your mouth, your throat or your stomach. The police officers are supposed to guard against this by observing you for 20 minutes. They are supposed to sit down and watch you for 20 minutes before giving the test. In all the years that I have been defending, or for that matter prosecuting, DUIs, I don’t think I’ve ever encountered an officer who actually did that. They are far too busy to fool around with things like that. They will check the box, it said they did, but it does not happen and I’m not sure they could even tell if it did happen. But that is a safeguard.
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