Breathalyzers: Defects Then/Failures Still

Breathalyzers have had a long history of controversy over their effectiveness and validity when used as evidence in a court of law. The author details their history of failure and malfunction as well as their current problems.

Breath Testing has become a tool frequently used by police officers throughout the United States. The questions remain: 1. Just how accurate are these machines? 2. How important are they to a prosecutor in a prosecution for operating a motor vehicle, or other motorized device, under the influence of alcohol (DWI/DUI)? And 3. Where can their reliability as accurate predictors of true blood alcohol content be attacked?

Where does breath testing fit within a DWI/DUI investigation? The breath test is relied upon by jurors as the God of evidence. Most citizens believe if an officer received a reading of .08% or greater from his administered breath test the defendant was surely impaired by alcohol. A result of .08% or more may be a legal inference but the publicity has done its job, you’re guilty now prove you're not guilty. Many jurors upon hearing the Breath Alcohol Content (BAC) is .08% or greater, at the beginning of trial, conclude improperly that the case is over and the defendant has lost his case As will be seen below, reliance by the general public is seriously misplaced and the validity of this blind conclusion cannot be justified.

To properly address breath testing and how it fits within the framework of a DUI investigation the reliance upon field sobriety testing must also be briefly considered because what is observed by an officer must by definition fit the picture of impairment.

Field sobriety testing is completely subjective. A trained officer is looking for errors within a myriad of possibilities while the test taker is performing as well as is possible under the rigors of a stressful and fearful event, performing foreign tests described and demonstrated by less than perfect biased test giver. The giver is only interested in the errors he has been trained to focus upon while the performer only cares about how well he can perform. (Many of the questions asked by officers before any testing are designed to discover unique problems that may affect a person’s performance on the pending test. The degree to which an officer considers the answers he receives from his subject is variable to each officer) The true performance is not always reported, The same can be said of breath testing results.

1) Precursors to breath machines and their ilk

The concern with the affect of alcohol upon a person was first considered by Francis E. Anstie, M.D. as early as, 1874. Anstie concluded a person could consume as much as 1.5 ounces of ethanol per day without any ill effects. That amounts to two and one-half (2 1/2) standard U.S. drinks. ( A standard drink can be defined as: one and one half ounce 80 proof shot; one twelve ounce beer; or a five ounce glass of wine.)

Arthur R.Cushny M.D., from Scotland, followed and in the early 1920”s observed the exhalations of volatile substances (alcohol) from the lungs is analogous to their evaporation from solutions in water. He concluded the concentration of alcohol in the blood could be predicted from the concentration of the alveolar air (respiratory gases in the deep lung).

In, 1927, Emil Bogen collected air into a football bladder and completed an analysis for alcohol by passing two liters of this collected breath through a solution of potassium dichromate and sulfuric acid.

It was Bogen who first observed one of the principal flaws in every subsequent breath testing instrument up to the present day. Bogen observed, as soon as the disrupting factor of alcoholic liquor still in the mouth is removed which occurs usually within fifteen (15) minutes after consumption, absent hiccuping or belching and that the alcohol content may be evaluated to predict the degree of intoxication.

The observation made by Bogen has remained credible through today nearly 90 years later.

In today’s world before a police officer collects a valid test with a breath testing machine, fixed or portable, the person submitting the test must be continuously observed for a period of 15 minutes before the test is attempted. Further, if the subject to be tested during this observation period burps, belches, vomits, drinks or smokes during this observation period the observation must be restarted before the test is completed.

A failure to observe these rules will be used to vitiate the reliability of the test itself.

In, 1930, Liljestrand and Linde observed the breath alcohol concentration (BrAC) and the blood alcohol concentration were similar and that 1cc. of blood contained as much alcohol as is contained in 2 liters of air. It was after this observation that many people began to work on a prototype of a breath testing apparatus.

2) Breathalyzer development “The drunkometer”

In, 1937, Rolla N. Harger, a biochemist, invented what he named the drunkometer. The Drunkometer used a sample of expired breath collected in a balloon which was passed through a dilute solution of potassium permanganate in sulfuric acid until the color was removed. (This combination was later changed by Kurt Dubowski). Balloon machines of this type were still being used through the early 1970”s and although their unreliability today is well known testimony by criminalists of the day about the test's accuracy the machine convicted uncountable citizens.

It must be here observed with the end of prohibition drivers on the highways became increasingly aware of the danger drunken drivers posed and the increase of traffic fatalities spurred interest in a portable breath machine. Law enforcement needed a tool to help control drunk driving.

Harger joined with Professor Robert Borkenstein and quickly learned the drunkometer needed stabilization and new succeeding generations of breath testing equipment was thereafter developed by them. Borkenstein produced the Intoximeter, and the Alcometer. Many other generations followed from different manufacturers but with technology that remains theoretically constant. Thus instruments identified as “Evidential Test Machines”, the multi generations of the “Alcosensors” and other portable breath instruments are scientifically identical in theory. (It is here interesting to note two things: 1. Indiana, the state from which Borkenstein hailed, was the first to introduce into a DUI/DWI investigation the tern blood/breath alcohol concentration. 2. The Alco-Sensor 5 breath testing machine received a recall of all 128 devices in Ventura County, California because of what was identified as a design flaw. However, it would be a mistake to assume any defendant can attack the science and be successful.)

As early as 1969 W.E. Smith recommended the adoption of breath testing equipment to the Association of Criminalists by saying: “It is concluded that the Breathalyzer meets the standards of good law enforcement when operated with the operational disciplines recommended”. The failure of operational discipline is the Achilles heel of breathalyzers.

3 Scientific concept of breathalyzers

It is only important to note here that since breathalyzers became common as a tool to ferret out DRUNK DRIVERS no Appellate Court decision has addressed the scientific veracity and analytical principals upon which the instrument is based. The only challenge which was close to successful appears to be found within the pages of State v Dounie in 1989 out of New Jersey. That case challenged the veracity of the partition ratio. (A partition ratio is a relationship of breath to blood. Essentially the conversion rate from breath to blood causes the breath to be multiplied 1 x 2100. The theory was a small error in the collection of alcohol in the breath could incorrectly reflect an unreliable blood result after that multiplication twenty one hundred times. Although there has been some new cases in this area the consideration of the partition ratio in California is too obscure to further dwell here. Suffice if some movement related to the scientific reliability of the instrument occurs in the near future a new article shall be generated on the prospects of success in a real life trial setting.) The conclusion today is the scientific theories addressed by the parties above noted are reliable.

The above conclusion, however, does not mean the instruments are reliable... they are not.

4) Breathalyzers produce false and inaccurate results

In, 1958, at the Symposium on alcohol and road traffic all members including the Chairman Robert Borkenstein observed a BAC level of .05% will definitely impair the driving ability of some individuals and the number of impaired individuals will continue to rise in a progressively higher proportion of these individuals until at a BAC of .10% all individuals are definitely impaired. Although California has adopted the presumptive level of .08% to identify an individual impaired by alcohol, even today not all are in agreement.

Because it is recognized errors in the application of breath instruments that produce invalid and unreliable results the balance of the space herein is consumed by how and why results produced can be inaccurate.

1. Breath machines are responsive to temperature and will provide inaccurate readings if not calibrated to adjust to a change in ambient temperature.

2. The pattern of breathing may affect the validity of a test. Holding your breath for 30 seconds could result in an increase of a BAC of .07% to .081% or more. Dr. Hystala, at the University of Washington believes the process of hyperventilation could free molecules of alcohol attached to the trachea thereby reflecting a higher inaccurate breath alcohol reading. Some believe this activity lowers the BAC.

4. Research has shown breath tests (BrAC) are higher than blood tests (BAC) by approximately 15%. (The requirements of California, Title 17, allow a variance in breath testin of +/- .01.)

5. The machine used, and all of them, must be regularly tested and calibrated by California law. Although the crime labs and police departments have a protocol in place, each machine rendering a test result, must be checked to verify accuracy.

6. If a breath test taker is on a diet (Watkins) or if he is a diabetic or undiagnosed diabetic The National Highway Traffic Safety Administration, (NHTSA) has found these people acetone level can be hundreds or even thousands of time greater than in a normal person. Acetone will test as ethanol in the breath test machine. (It should be noted as many as three of ten people are undiagnosed diabetics. Get checked out!).

7. Many substances found in the environment of every day life could present for a test taker a false positive. People who work with paint, lacquer, cleaning solvents, ethers, and other alcohols should be concerned of a false positive test.

8. The Partition Ratio, (discussed above) remains a valid concern. An individuals partition ratio varies from 1300:1 to 3000:1. The machine assumes all persons partition ratio is 2100:1 and computes the sample trapped by the testing machine and multiplies that result by 2100 times. How much different would your breath result be it a true number was substituted for the fictional one?

9. A breath test taken during the absorptive phase will present inaccurate results. The absorptive phase is another way of saying alcohol is still entering your blood stream. Your BAC is still increasing. ( 1.This reality can more frequently be asserted if those people tested didn’t lie so much. To impress the officer with implied sobriety most people put the time of their last drink as a couple of hours ago. Wrong direction. “I just finished drinking minutes ago.”….. would be better and more accurate. 2. A breath test administered during the absorptive phase could reflect a BAC of .11% while the real BAC was but .04%.

10. Mouth alcohol can contaminate an otherwise valid test. Mouth alcohol is presumed to be gone from the mouth after 15 minutes. The officer is required to observe you for that period by California law to insure the subject does not burp, belch, regurgitate, drink, or smoke during that period. Officers try to shortcut this requirement by claiming he began his observation at the time he got the subject out of the car, some make up any time to begin the observation. Certainly case law showing the officer talking to his partner outside the police car with the arrestee inside the car and the window down but partially was insufficient to produce a valid test. (The burp referred to here must bring fluids from the stomach to the mouth).

11. Mouth alcohol has been found in other studies where the substance was not introduced to the test by the test taker. In the study of Trayford a defective bridge in the mouth trapped alcohol and through hyperventilation introduced additional alcohol to the breath test. (periodontal disease also traps and secrets alcohol during testing.)

12. Acid reflux, is caused when stomach material comes into the mouth because of a defective or herniated valve between the stomach and the trachea. This condition creates an invalid test because mouth alcohol is present at the time of the test.

13. The time of driving is the important factor in breath testing. Fortunately most people do not submit to a breath test at the moment an officer appears. (It’s probably better to request a blood test and forgo breath testing at all.) However, any test given will and must be related back to the time of driving. (To calculate the Widmark type formula the following elements are considered. a. the time of the test. b. the result of the test. c. the time of driving. d. the time of the last drink. and e. the time of the last food eaten. This computation is used in every DUI/DWI case and is known as retrograde extrapolation.)

14. Most machines today avoid the problems of Radio Frequency Interference (RFI) but the constant use of officer radio traffic could affect the test validity.

15. Long term smokers have an inherently higher BrAC because of the presence acetaldehyde. There are also reported false positives in the consumption of some bread products.

If a blood test is not possible and the breath test is the only available choice be aware that all the experts agree the science is good but if the machine is not properly calibrated, or temperature has affected the reading, or an observation period has not been properly observed, or if you had mouth alcohol, or an unknown condition or malady you could stand to be convicted by a jury of you peers on invalid evidence just like those citizens who were convicted by the drunkometer, so many years ago.

Moral: Take a blood test!

By Law Offices of Randy Collins, California
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ABOUT THE AUTHOR: Ronald MacGregor
Ronald D. MacGregor, Esq., graduated from University of the Pacific, McGeorge School of Law (1973). He received his Constitutional Law Education from United States Supreme Court Associate Justice Anthony Kennedy and began practicing law in Northern California.

In 1980 he began the first volunteer alcohol program for DUI violators in Monterey County.

He has numerous published cases not the least of which was the finding by the Appellate Court that, “,,,,there is no such crime as attempted involuntary manslaughter". He instructed new lawyers in Administrative law and Department of Motor Vehicle Law for the Orange County Bar Association for three years and to date, in Orange County, has represented over 10,000 DUI related defendants.

He is a Partner at MacGregor and Collins, LLP.

Copyright Law Offices of Randy Collins

Disclaimer: Every effort has been made to ensure the accuracy of this publication at the time it was written. It is not intended to provide legal advice or suggest a guaranteed outcome as individual situations will differ and the law may have changed since publication. Readers considering legal action should consult with an experienced lawyer to understand current laws they may affect a case. For specific technical or legal advice on the information provided and related topics, please contact the author.

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