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Are Intoxilyzer 5000 BAC results accurate?

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When a police officer arrests you for a Virginia DUI, restrains your wrists with metal handcuffs, robotically reads the Miranda Law then pushes on your head as you wobble into the back seat of his cruiser, you’d like to be sure that the station breath testing machine you have "consented" to take is accurate.

If your presumption of innocence becomes a presumtion of guilt based on results due to a “failed” reading from the Intoxilyzer 5000 -- the machine used in Virginia and 20 other states and commonwealths to determine blood alcohol concentration (BAC) levels – you may hesitate to ever drive again after just one ‘social’ drink.

It’s frightening to think a reading from a machine less sophisticated than the computer you are reading to view this article can harness your freedom and keep you holed up in a cell overnight. But it can.

Why is it precarious? Simple. In any laboratory, results are determined through a series steps to determine probabilities. A lab worker “arrives” at a decision with plus-or-minus waive rings. It’s never definitive, never exact and never 100% foolproof. Autopsists cross-check exhaustedly so exhuming bodies through court orders isn’t a common occurrence. Biopsies take time so technicians can cover each other’s findings. They almost work to prove the other wrong, just to be sure of the result. Still, it may not be exact.

One Fuzzy Testimonial

Read the following excerpt from the website of CMI Inc., the manufacturer of the Intoxilyzer 5000. This mission statement exhaustedly explains the value of the product that plays a key role in determining one’s guilt or innocence.

“When IR (infrared) light of a particular frequency passing through a chamber with no alcohol present strikes a detector, a certain voltage level is created. This can be called X. As an alcohol sample is introduced into the chamber, some of the IR light is absorbed or attenuated. As the alcohol level in chamber increases, the amount of light able to pass through the chamber and strike the detector decreases. At the end of the sample, a very different amount of light is striking the detector creating a different level of voltage. This new level of voltage can be called Y. If the amount of IR light passing through the chamber with no alcohol present can be determined—X, and the amount of light passing through the chamber with alcohol present—Y—can be determined, the difference between the two will represent the concentration of alcohol in the breath sample. The more alcohol present, the greater the absorption.”

Here’s more company “proof.’

“In the I-5000 (and 1400), a quartz lamp generates IR energy which travels through a sample chamber containing the subject’s breath. Upon leaving the chamber, a lens focuses the energy onto a chopper wheel containing up to five narrowband IR filters. The IR energy passed by the filters is focused on a highly sensitive photo detector which converts the IR energy into electrical pulses. A microprocessor then interprets the pulses and calculates the Blood Alcohol Concentration which is then displayed on the instrument.”

With Prison Pending, There’s No Wiggle Room

Reference the bold face copy. In CMI’s text, “focusing, determining, converting and interpreting” ascertains variable results, not constants.

CMI calls the I-5000 “highly sensitive” but how exact? And sensitive to what extremes? Sensitivity manifests in assumptions not precision. This state-of-the-art machine utilized by police departments interprets, focuses, represents, converts and calculates. Does that sound convincing? “Very different,” “new,” and “different” are actual adjectives used by the manufacturer to describe the supposed “pinpoint-perfection” readings from this component of justice.

It’s been surmised by medical experts that fever, fatigue, metabolic rates, hyperventilation, appetite, mood swings and sheer anxiety over “taking the test” can affect a BAC reading and certainly impact performance on a field sobriety test. So who is to say that alcohol, alone accounts for the hundredths-of-a-percent reading of this machine. So instead of touting the benefits of the I-5000 engineers should give it closer examination. After all, one’s freedom is directly dependent on this product. Labs should inspect and re-inspect its findings and research alternative measures. Continued use of the I-5000 tugs at the blindfold of Lady Justice.

Bob Battle
100% of my practice is devoted to serious traffic defense and criminal litigation in state and federal courts
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