It is important to understand the inner workings and the theory behind breath testing in order to understand how it can be wrong. It behooves all attorneys that deal with breath test evidence to attend special seminars and obtain practical hands on experience with these devises. The breath test is an important part of many DWI trials and is a key focus for both the State and the defense. The following list is intended to summarize my top ten reasons why a breath test on the Intoxilyzer 5000EN as used in New Hampshire may be false:
I. Machine error
II. Temperature variation
IV. Breathing pattern
VI. Lack of specificity
IX. Operator error
X. Calibration errors
1. Machine Error
No machine is ever perfect and even the manufacturer CMI, Inc has brochures and sales materials available on line that detail that detail the Intoxilyzer 5000EN "is better than federal requirements, ?3% or ?.003 BrAC," http://www.alcoholtest.com/prodinfo/I-5000.pdf. The CMI, Inc. website also proudly boasts that the Intoxilyzer 5000EN contains "no unproven technology here!" http://www.alcoholtest.com/intox5000.htm. Aside from the obvious all machines have glitches, this advertising campaign will allow you to compare the improvements made with CMI's Intoxilyzer 8000 and other breath testing devices that use both IR and EC methods for comparison (Draeger's Alcotest 7110). Clearly the Intoxilyzer 5000EN is not the most advanced breath testing device on the market or even produced by CMI.
I have had many cases challenging the close test cases and even the New Hampshire Forensic Laboratory personnel will acknowledge that the Intoxilyzer 5000EN has a range of error of 10%.
2. Temperature Variation
One of the foundations of breath testing is Henry's Law which requires that temperature be constant. The New Hampshire Intoxilyzer 5000EN and Guth 2100 simulator are set up using 34 degrees Celsius. The New Hampshire regulations require that the simulator temperature be +/- .2 degrees Celsius again emphasizing the importance of temperature on breath testing. It is clear that New Hampshire is using 34 degrees Celsius as the temperature of expired breath.
However, studies have shown that the average temperature of expired breath is actually closer to 35 degrees Celsius. It has also been established that a one degree difference will result in an 8.6% overestimation of breath alcohol content compared to blood. Physiological Aspect of Breath-Alcohol Measurement, Alcohl, Drugs & Driving, Vol.6 No. 2, A.W. Jones. International Association for Chemical Testing (IACT) Newsletter Vol. 9, Number2, July 1998, Dale A. Carpenter, Ph.D. and James Buttram, Ph.D.
Hematocrit levels are a ratio of the whole blood composed of red cells and is correlated with the aqueous content of the blood. The higher the hematocrit; the lower the concentration of water in the blood and vice versa. The Chemical Basis of the Breathalyzer, Journal of Chemical Education, Vol. 76, No. 3, pp. 259-261, March 1990, Domink A. Labianca. This means that if a person has higher hematocrit levels they have more solid in their blood, less water and therefore a higher concentration of alcohol. It has been determined that with breath tests, normal variation in the hemocrits of test subjects "can produce errors in the 10-14% range." The Chemical Basis of the Breathalyzer, Journal of Chemical Education, Vol. 76, No. 3, pp. 259-261, March 1990, Domink A. Labianca. Payne, J.P., Hill, D.W., Wood, D.G.L., Nature, 1988.
4. Breathing Patterns
In New Hampshire the police are trained to tell subject to blow when told and to keep blowing while there is a tone made by the machine. Frequently the police will encourage a person by saying "blow, blow, blow." There is a true statement that the harder you blow the higher you go. This is due in large part to a person holding their breath prior to blowing and then producing more volume and warmer breath. Studies have shown that "the subject's manner and mode of breathing just prior to providing breath for analysis can significantly alter the concentration of alcohol in the resulting exhalation." Physiological Aspect of Breath-Alcohol Measurement, Alcohl, Drugs & Driving, Vol.6 No. 2, A.W. Jones.
The same study found that hyper ventilation lowers the breath alcohol concentration by as much as 20% compared with a single moderate inhalation and forced exhalation used as control tests. It also found that holding breath for a short time (20 seconds) before exhaling raises a test.
5. Partitition Ratio
The Intoxilyzer 5000EN measures breath not blood which requires a conversion ratio or partition ratio to be programmed. As previously stated there are studies showing a blood to breath partition ratio from 900:1 to 3400:1. Alobaidi, T.A.A & Payne, J.P. Significance of Vatiation in Blood-Breath Partition Coefficient of Alcohol, British Medical Journal, 1976; Mason, M. F. & Duboski, K.M. Breath Alcohol Analysis: Uses, Methods and Some Forensic Problems, Journal of Forensic Sciences, 1976; Yamamoto, K & Ueda, M. Studies on Breath Alcohol Analysis For the Estimation of Blood Alcohol Levels, Journal of Forensic Sciences, 1972,
It has been shown that 10-15 minutes after drinking or during the absorptive phase of alcohol metabolism breath testing will overstate the breath alcohol concentration by 300%. It has also been shown that even 90 minutes after consumption some people are still in the absorptive phase and their breath alcohol readings will be overestimated.
6. Lack of Specifity
The Intoxilyzer 5000EN has 3 filters designed to detect only three methyl containing interferents which may occur on a person's breath. There are literally over 100 compounds which may exist in a person's expired breath many within the IR band width that can cause an additive affect to a breath test. The problem is that the Intoxilyzer 5000EN is unable to identify alcohol to the exclusion of all other chemical compounds. This stems from the Intoxilyzer 5000EN only detecting the methyl group of the alcohol molecule instead of the entire molecule. This is probably the largest single difficulties in producing an accurate breath alcohol concentration
It is essential to learn what a person does for a living as they may be exposed to various solvents or distillates which may interfere with a breath test. Additionally it is important to obtain a medical history from all subjects of breath testing to learn about medications for asthma, diabetes or other conditions that may require.
The Intoxilyzer 5000EN is measures 82.2 cc of breath and produces a result that is in grams per 210 liters. This by it's very nature means that it must multiple the number by over 1000 to arrive at the grams per 210 result. So this means that if there were even just a very minuscule contamination in the chamber it would be multiplied by over a 1000 to produce a noticeable error.
The extrapolation errors present themselves when there is contamination of a breath sample. This can frequently happen due to issues like GERD, dentures, chewing tobacco, or any foreign matter which comes into contact with the mouth.
Radio frequency interference (RFI) is electromagnetic interference that affects radio frequency bands from 100kHz to 5 GHz. The RFI antennae in the Intoxilyzer 5000EN is contained in the heated breath tube and was based on radio frequencies used in the 1970's and 1980's. The band widths that are currently being used are much different than those when the Intoxilyzer 5000EN was built. Simply put this RFI detector is not reliable. The older band widths are hardly used anymore and the detector is essentially blind to a substantial portion of the band widths used by police radios, cell phones, dispatchers radios, and radar units.
Another source of problems is that the RFI detectors are rarely calibrated in the real world by using multiple devises, instead the lab personnel will send a RFI signal that the Intoxilyzer 5000EN is programmed to receive. Additionally, the "test" is done with the Intoxilyzer 5000EN turned on but not during an actual test to determine if it affects the test
9. Operator Error
One of the most interesting aspects of any court case is that nothing ever goes the way it is planned. In part that is because we are dealing with human beings. The operators of the Intoxilyzer 5000EN are police officers and they have been certified to conduct the tests. However, it never ceases to amaze how a relatively automated process can still be corrupted by a human being.
The administrative rules set out the minimum requirements and it is essential that they be followed to the letter. If the operator fails to perform a proper 20 minute observation period, change a mouthpiece, label the independent sample tubes, types in the wrong simulator serial number or any other countless errors, the test results may be unreliable, inaccurate, and inadmissible.
The New Hampshire State Forensic Laboratory is responsible for maintaining and calibrating the Intoxilyzer 5000EN and the Guth simulators consistent with the administrative rules. There are specific requirements that must be met and certifications that are supposed to be provided in order for the tests to be admissible. Mistakes happen and it is imperative that the codes be adhered to strictly. The laboratory personnel do make mistakes and if they do then the tests are unreliable, inaccurate and inadmissible.
Conclusion, Breath Testing is Fallible
Breath testing is likely here to stay in New Hampshire. There are many thousands of dollars and hours invested in the program. It is unclear if New Hampshire will follow the current trend and consider purchasing newer more advanced breath testing devises, however, a good background in the history, science, methodology as well as knowledge about some of the problem areas will enable a DWI defense lawyers to represent client and win DWI cases. I take pride in knowing the science and inner workings of the breath machines to help my client's win their cases. Just because a test result is over the legal limit does not mean that a person is guilty. I have attended multiple trainings involving breath testing so that I have gained the experience and to completely understand the strengths and weaknesses of breath testing in your case. Do not hesitate to contact me regarding a defense in a breath test case.
Our Rating is calculated using information the lawyer has included on their profile in addition to the information we collect from state bar associations and other organizations that license legal professionals. Attorneys who claim their profiles and provide Avvo with more information tend to have a higher rating than those who do not.
What determines Avvo Rating?Experience & background
Years licensed, work experience, education
Legal community recognition
Peer endorsements, associations, awards
Legal thought leadership
Publications, speaking engagements
This lawyer was disciplined by a state licensing authority in .
Disciplinary information may not be comprehensive, or updated. We recommend that you always check a lawyer's disciplinary status with their respective state bar association before hiring them.