DUI BLOG

With more than a little federal coercion, all states have now passed laws making it a criminal offense to drive with .08% alcohol in your blood. And most people suspected of violating that law are given breath tests to determine their blood-alcohol concentration (BAC). The breathalyzer will take a small sample of the suspect’s breath and estimate how much alcohol is in it — and, then, estimate how much may be in the blood.

And what that machine says is pretty much the end of it. There will be no second tests. There will be no cross-examination of the machine. Are these machines so reliable and accurate that we have permitted them to become judge and jury?

Scientists universally recognize an inherent error in breath analysis, generally of plus or minus .01%. That means that if everything is working perfectly (an unlikely scenario), a .13% breathalyzer test result can be anywhere from .12% to .14%.This has been acknowledged by courts across the country (see, for example, People v. Campos, 138 Cal.Rptr. 366 (California); Haynes v. Department of Public Safety, 865 P.2d 753 (Alaska); State v. Boehmer, 613 P.2d 916 (Hawaii), recognizing an even larger .0165% inherent error).

What does that tell us about the accuracy of these breathalyzers? Well, let’s take a test result of .10%. Taking inherent error into consideration — and assuming the machine was working perfectly, the officer administers the test correctly, and the suspect’s physiology is normal and perfectly average — the true BAC could be anywhere from .09% to .11%. In other words, the true BAC can be 10% in either direction — or, put another way, anywhere within a 20% margin of error.

These machines have a 20% margin of error?

That’s right. A person accused of driving with over .08% BAC can be convicted by a machine which, if everything else is perfect, has a built-in 20% margin of error. Would you be comfortable with an airline pilot who worked with a 20% range of error? A brain surgeon? A bank teller? How about the sole evidence in a criminal case where guilt must be proven beyond a reasonable doubt?

Close enough for government work.

Want to trick that breath machine into a false reading? Not that difficult: just vary your breathing pattern.

As I’ve indicated in earlier posts, these breath machines which determine guilt or innocence in DUI cases are not exactly the reliable devices that law enforcement would have us believe.Yet another example of that unreliability is the fact that the results will vary depending upon the breathing pattern of the person being tested.

This has been confirmed in a number of scientific studies. In one, for example, a group of men drank moderate doses of alcohol and their blood-alcohol levels were then measured by gas chromatographic analysis of their breath. The breathing techniques were then varied.The results indicated that holding your breath for 30 seconds before exhaling increased the blood-alcohol concentration (BAC) by 15.7%. Hyperventilating for 20 seconds immediately before the analyses of breath, on the other hand, decreased the blood-alcohol level by 10.6%. Keeping the mouth closed for five minutes and using shallow nasal breathing resulted in increasing the BAC by 7.3%, and testing after a slow, 20-second exhalation increased levels by 2%. "How Breathing Techniques Can Influence the Results of Breath-Alcohol Analyses", 22(4) Medical Science and the Law 275.For another study with similar findings, see "Accurate Measurement of Blood Alcohol Concentration with Isothermal Breathing", 51(1) Journal of Studies on Alcohol 6.

Dr. Michael Hlastala, Professor of Physiology, Biophysics and Medicine at the University of Washington has gone farther and concluded:

"By far, the most overlooked error in breath testing for alcohol is the pattern of breathing….The concentration of alcohol changes considerably during the breath…The first part of the breath, after discarding the dead space, has an alcohol concentration much lower than the equivalent BAC. Whereas, the last part of the breath has an alcohol concentration that is much higher than the equivalent BAC. The last part of the breath can be over 50% above the alcohol level….Thus, a breath tester reading of 0.14% taken from the last part of the breath may indicate that the blood level is only 0.09%." 9(6) The Champion 16 (1985).

Many police officers know this. They also know that if the machine contradicts their judgement that the person they arrested is intoxicated, they won’t look good. So when they tell the arrestee to blow into the machine’s mouthpiece, they’ll yell at him, "Keep breathing! Breathe harder! Harder!" As Professor Hlastala has found, this ensures that the breath captured by the machine will be from the bottom of the lungs, near the alveolar sacs, which will be richest in alcohol. With the higher alcohol concentration, the machine will give a higher — but inaccurate — reading.

It may not surprise you to find out that alcoholics arrested for DUI will generally have higher blood-alcohol readings. It may surprise you, however, to learn that alcoholics will generally have higher blood-alcohol readings BECAUSE they are alcoholics….. That’s right. It’s because the physiology of alcoholics is different in some important respects.

One of those is that their bodies produce more acetaldehyde — far more. Acetaldehyde? That’s a compound produced in the liver in small amounts as a by-product in the metabolism of alcohol. Unfortunately, alcohol in the lungs has been found to metabolize there as well as in the liver — and to produce acetaldehyde there.

The amount of acetaldehyde produced in the lungs (to then be breathed into the breathalyzer) varies from person to person. "Origin of Breath Acetaldehyde During Ethanol Oxidation: Effect of Long-Term Cigarette Smoking", 100 Journal of Laboratory Clinical Medicine 908. But in a study focusing on alcoholics, researchers discovered that the amount of acetaldehyde in the breath and blood of alcoholics was 5 to 55 times higher than that in nonalcoholics. "Elevated Blood Acetaldehyde in Alcoholics and Accelerated Ethanol Elimination", 13 (Supp 1) Pharmacology, Biochemistry and Behavior 119.

End result: since breathalyzers can’t tell the difference between alcohol and acetaldehyde (see earlier post, "Why Breathalyzers Don’t Measure Alcohol"), alcoholics will usually have higher blood-alcohol readings.

Remember that "new car smell"? The great scent inside of that new car you bought a couple of years ago? It could get you charged with DUI…. Consider an excerpt from the Reuters news agency (Sydney, December 9, 2001):

"Australian scientists have warned that the reassuring smell of a new car actually contains high levels of toxic air emissions which can make drivers ill. A study by Australia’s main scientific body, the Commonwealth Scientific and Industrial Research Organization (CSIRO), found high levels of toxic emissions in cars for up to six months and longer after they leave the showroom… The toxic emissions include benzene, a cancer-causing toxin; acetone, a mucosal irritant; ethylbenzene, a systemic toxic agent; and xylene isomers, a foetal development toxic agent…."

So what has this got to do with breath tests? Well, one of the compounds you were actually smelling was acetone. As has been discussed in earlier posts ("Why Breathlyzers Don’t Measure Alcohol"), acetone is one of many chemical compounds which Breathalyzers will mistakenly report as alcohol. See the reasearch reported in such scientific articles as "The Likelihood of Acetone Interference in Breath Alcohol Measurements", 3 Alcohol, Drugs and Driving 1, and "Excretion of Low-Molecular Weight Volatile Substances in Human Breath: Focus on Endogenous Ethanol", 9 Journal of Analytical Toxicology 246.

And no, you don’t have to drink the stuff. Simply absorbing it through your skin or inhaling it can result in measurable levels of the compound in your body for hours or even days, which will be continually expelled in the breath….. and possibly into a judge-and-jury breathalyzer.

Folks who have read my recent post, "Why Breathalyzers Don’t Measure Alcohol", seem quite surprised to find out these DUI machines are not as reliable as MADD and law enforcement agencies would have us believe. In fact, the manufacturers of these things refuse to even warrant them to do what they’re supposed to: accurately measure blood-alcohol levels (see my earlier post, "Breathalyzers: Why Aren’t They Warranted to Measure Alcohol?")

So how reliable are these "breathalyzers" that determine a person’s guilt or innocence in DUI cases? And just what DO they measure?

Well, thousands of different chemical compounds, according to scientists. Gasoline for one. Consider an article appearing on the front page of the Spokane Spokesman-Review (August 24, 1988), in which a person sitting in jail awaiting trial for DUI claimed that he had nothing to drink. He said he had run out of gas and had been siphoning gasoline from a container into his tank before being stopped by the officer and arrested. In siphoning, he had sucked on the hose to get it started and accidentally swallowed a small amount of the gasoline. He claimed that this must have caused the later high breathalyzer reading. The individual finally talked the sheriff into a demonstration to prove his story.

Taken from his cell after one week of incarceration, he swallowed a cup of unleaded gasoline and then blew into the breath machine — in this case, an "Intoximeter 3000". The results? After 5 minutes, the reading was .00%…..after 10 minutes, .04%……after 20 minutes, the Intoximeter registered .31%…..and after one hour, the reading was .28%. Even after three hours, the person still blew a .24% on the machine — three times the legal limit! (A quick call from the sheriff to a local gasoline distributor confirmed that gasoline contains no alcohol.)

This was not a freak occurrence. The results have been scientifically verified in a study conducted by CMI, Inc., the manufacturer of a competing breath machine, the "Intoxilyzer 5000", and reported in 8(3) Drinking/Driving Law Letter 6. The CMI technicians mixed a simulator solution of 800 micrograms of gasoline with 500 milliliters of distilled water, then introduced it into their machine. The solution produced readings of .619%, .631% and .635% — or about eight times the legal limit for "alcohol" levels.

You don’t have to drink gasoline to get a reading on the breathalyzer. Breathing the fumes will do it. Like at a gasoline pump.

A citizen arrested for DUI usually has the right to choose between taking a breath test or a blood test. There is, of course, a third choice: refuse to take either. The individual can do this, but there are consequences: he will face an increased jail sentence or a longer driver’s license suspension — or, in most states, both. The problem is that some police just won’t take "no" for an answer.

An increasing practice among law enforcement agencies is to simply ignore this third choice and forcefully take blood from the arrestee (although some states have banned this practice). By doing this, they can "have their cake and eat it, too": blood is obtained for testing– and the suspect still suffers the heavier sentencing for having refused. So, just how much "force" will the courts permit?

Or looking at this from the legal view, drawing blood is considered a Search of the person and, therefore, must be "reasonable" under the Fourth Amendment to the U.S. Constitution. Which still leaves the question: What is "reasonable" force?

The United States Supreme Court addressed this issue in Rochin v. California (342 U.S. 165), where a drug suspect was unconscious and the police forced open his mouth and pumped his stomach to get drugs. Such conduct is not permissible, the Court said, if it "shocks the conscience". This vague "shocks the conscience" standard — if it is a standard — was later applied by the Supreme Court in a drunk driving case: The blood, the Court said, must be taken under "humane and medically acceptable" circumstances. Schmerber v. California (384 U.S. 757). [As anyone who has watched certain videotapes knows, California seems to have recurring problems with heavy-handed police.]

Humane and medically acceptable circumstances…..Shocks the conscience…..

Well, let’s take a look at what police and courts in California have decided this all means. In Carleton v. Superior Court (216 Cal.Rptr. 890), the California Court of Appeals was confronted with a case where the arrested citizen was pinned down by six police officers, a needle jammed into him and blood forceably withdrawn. The Court saw nothing wrong with this:

"Although this degree of force may approach the brink of excessiveness, it was not excessive. Carleton’s self-induced brief physical restraint before and during the withdrawal of a blood sample is not conscience shocking."

One wonders what it would take to go over that "brink"…..

That’s right: Breathalyzers don’t actually measure alcohol. What they actually detect and measure is any chemical compund that contains the methyl group in its molecular structure. There are thousands of such compounds — including quite a few which can be found on the human breath. And this machine that determines a person’s guilt or innocence will "see" all of those chemicals as alcohol — and report a falsely high "blood-alcohol" concentration (BAC).

Most breath machines used in DUI cases by law enforcement today employ a technology called "infrared spectroscopy". The DUI suspect breathes through a tube connected to the machine and a breath sample is captured in a small "sample chamber" inside the machine. Then beams of infrared energy are shot through the captured breath sample. If there are any compounds containing the methyl group, they will absorb some of this energy; the more of the chemical compound in the breath sample, the more energy is absorbed. The more energy that is absorbed, the less infrared energy that reaches sensors at the other end of the sample chamber. And the less energy that is detected by the sensors, the higher the "blood-alcohol" reading.

Problem: the machine is designed to simply assume that the chemical compound absorbing the energy is alcohol. If a person has any of these other compounds on his breath, called "interferents" by the engineers, he will get a falsely high BAC test result. And if there are two or three such compounds on his breath, the machine will read a cumulative result: it will add them up and falsely report the total as the blood-alcohol level.

So what kinds of compounds may be on a person’s breath that can cause false BAC readings in a DUI case? In one study of eight men, 69 different compounds containing the methyl group were discovered. "Trace Composition of Human Respiratory Gas", 30 Archives of Environmental Health 290. In another study invoviing 28 subjects, researchers found that teh "combined expired air comprises at least 102 various organic compounds of endogenous and exogenous origin". "Characterization of Human Expired Air", 15 Journal of Chromatographic Sciences 240. And Camnadian scientists have discovered over 200 such compounds. "The Diagnostic Potential of Breath Analysis", 21(1) Clinical Chemistry 5.

What are these compounds? Are there any on my breath?

Well, for starters, diabetics with low blood sugar can have high levels of acetone — which is "seen" as alcohol by Breathalyzers. And scientific studies have found that people on diets can have reduced blood-sugar levels, causing acetone hundreds of times higher than found in normal individuals. Frank and Flores, "The Likelihood of Acetone Interference in Breath Alcohol Measurements", 3 Alcohol, Drugs and Driving 1. And there are many other so-called "interferents". See, for example, "Excretion of Low-Molecular Weight Volatile Substances in Human Breath: Focus on Endogenous Ethanol", 9 Journal of Analytical Toxicology 246.

If you are a smoker, your Breathalyzer result is likely to be higher than expected. The compound acetaldehyde — reported by the Breathalyzer as "alcohol" — is produced in the human body as a by-product in metabolizing consumed alcohol, and eventually passes into the lungs and breath. Researchers have discovered that levels of acetaldehyde in the lungs can be 30 times higher in smokers than in non-smokers. Result: higher BAC readings on the machine.

And then there are the industrial compounds: paint, glue, gasoline, thinners, and other compounds contain the methyl group. No, you don’t have to drink the stuff: simply absorbing it through your skin or inhaling the fumes can result in significant levels of the chemical in your body for hours or even days, depending upon the "half-life" of the compound. So if you’ve painted a room or siphoned some gasoline in the last day or two, don’t breath into a Breathalyzer.

Some law enforcement officials say that this is not a problem, claiming that levels of the compound would have to be at toxic levels to raise a breath test result to .08% or higher. These officials are displaying their ignorance of the science involved — specifically, of the partition ratio. This is the ratio of the compound found in the breath to that found in the blood. With ethanol, the ratio is 2100-to-1, which means that, on average, there will be 2100 units of alcohol in the blood for every unit found in the breath.

These officials are using this ratio for all compounds, but every compound has its own ratio. Toluene (found in paint, glue, thinners, cleaning solvents. etc.), for example, has a partition ratio of only 7-to-1; a far greater amount of toluene in the blood will pass into the breath, and so a much smaller amount in the body will have a far greater impact on the breath machine.

How serious is a DUI conviction? Well, among other things, it can get you barred from entering some countries, including our neighbor to the north….. as President Bush discovered.

Under Canada’s laws (Section 19(2)(a.1) of the Immigration Act), anyone who has been convicted of drunk driving is a member of an "Inadmissible Class" and his entry into the country would be a criminal and deportable offense. Period. This is a lifetime ban: President Bush’s 1976 conviction in Kennebunkport, Maine, would render him personna non grata. Same for Vice-President Cheney’s two DUIs in Wyoming.

However, Canadian law permits a person with a DUI on his record to be admitted into Canada if he has been successfully "rehabilitated". This requires applying for, and being granted, a "Minister’s Permit of Rehabilitation" from the government — but not until five years after all of the terms of the sentence have been completed (if there is a three-year probation, as is common, then it will take at least eight years). The government reviews the application, along with accompanying evidence, and applies a "rehab checklist" in deciding whether the individual has truly rehabilitated himself and should be permited to enter the country. This checklist includes evidence of genuine remorse, acceptance of responsibility, change in lifestyle, and stability in employment and family life.

As for President Bush’s little problem, the Canadian government decided to bypass all of this and simply granted him a special "pardon" permitting this unrehabilitated drunk driver into the country….for a limited period of time.

I have referred in many of my posts to a “DUI exception to the Constitution”, and have had numerous queries as to just what exactly this exception is.

There is, of course, no such “exception”. The term is one I have used for many years to characterize the increasing tendency in DUI cases to ignore the United States Constitution. It is easy for politically-sensitive legislators and judges to give in to the pressures of groups like Mothers Against Drunk Driving (MADD), particularly when there is no one to stand up for those whose rights are being violated. But the price is paid not only by the accused, but by all of us: it is the Constitution itself that is eroded. And the nature of our legal system is one of “precedent”: if it is permissible to ignore the Constitution in a DUI case today, then the precedent exists to ignore it in all cases tommorrow.

At some point I began using the term as the title of a lecture I’ve given to various groups of lawyers and laymen on the increasing danger to our Constitutional rights from the political pressures of well-intentioned but ignorant groups like MADD. The lectures have since been reproduced on a number of websites. For an example, see the transcript on Atlanta attorney William C. Head’s website.

You’ve just been arrested for DUI. And, like in the movies, the officer reads you the "Miranda" rights: "You have the right to remain silent", he tells you, "You have the right to an attorney" And then the very next thing he’s asking if you’ll take a breath or blood test.

Now, wait a minute, you think to yourself. He just said I have a right to remain silent. Why should I agree to take a test? The 5th Amendment says I don’t have to incriminate myself. Something’s not right here…. And anyway, you think, do I really have to take a test? Are those Breathalyzers accurate? Would a blood test be better? Well, he said I have a right to counsel: I’d better call my lawyer and get his advice before I decide wheher to take a test or not, and which one I should take.

So you tell the officer you wish to remain silent, and you want to make a call on your cell phone to your attorney. "Are you refusing to take a test?" he asks darkly. "I just want to talk to my attorney," you reply. "Your funeral," the officer says. Now what did he mean by that?

What he meant was that, depending upon the state, a refusal to submit to chemical testing will trigger increased penalties — mandatory jail terms and longer driver’s license suspensions over and above the usual DUI penalties — and may even be considered a separate criminal offense. And, in most states, the jury will be instructed by the judge that this refusal can be viewed as "consciousness of guilt".

Believing you have constitutional rights in a DUI case can be very dangerous. What happened was very common: "officer-induced confusion". Three apparently contradictory things are communicated to the (very frightened) person arrested for DUI: (1) you can remain silent and refuse to possibly incriminate yourself, (2) you can consult with a lawyer, and (3) you have to take a chemical test that may incriminate you. What would the normal person conclude? Well, let’s take a closer look at the laws involved here.

First, the "implied consent" law says a person driving on the state’s highway impliedly consents to a chemical test when requested by an officer. Second, the Fifth Amendment right to "remain silent", or not incriminate yourself, protects you from custodial interrogation, not from having to give physical evidence. Third, the U.S. Supreme Court has been vague on how the right to counsel applies in a DUI case (the well-known "double standard").

As a result, some states permit the right to counsel after an arrest; most, however, deny the arrestee any access to a lawyer in a DUI case until after the police are through with him — even if he is arrested, taken to the station, and held in handcuffs until he is tested (the post-arrest process can take up to two hours or more). So when the officer said you had a right to counsel, that wasn’t quite true. He should have said, "You have a right to counsel….usually, but since this is a DUI arrest you can’t talk to one for an hour or two". (As we say, "the DUI exception to the Constitution".)

What if you change your mind five minutes later and agree to take a test? Some courts have reasoned that if a short delay does not affect the value of the test, there is no good reason for not letting the suspect take the test. Most states, however, will not let you change your mind. As one appellate court bluntly put it, "One offer plus one rejection equals one refusal and one suspension". Dunlop v. DMV (156 Cal.App.3d 279).

Translation: tough luck all around. Granted it’s all very confusing, and even the courts don’t all agree, but you are going to be prosecuted and punished for refusing to take a test. Put another way, believing you really have a constitutional right not to incriminate yourself and to talk with an attorney in a DUI case can get you into a lot of trouble.