Understanding the Intoxilyzer 9000 and How It Works
The Intoxilyzer 9000, manufactured by CMI Inc., employs infrared spectroscopy with four filters to detect ethanol (alcohol) in your breath, focusing on the C-O vibration in the 9-micron region for high specificity. It analyzes deep-lung air to estimate your BAC, with readings above 0.08% typically leading to DUI charges. However, the device isn't foolproof. It can pick up "mouth alcohol"—residual alcohol lingering in your oral cavity from recent sources, rather than alcohol absorbed into your bloodstream from drinking. This is where everyday items like chewing gum come into play, creating false positives that don't reflect your true intoxication level.
The GBI's evaluation, conducted by the Division of Forensic Sciences, tested the Intoxilyzer 9000 extensively, including its performance in laboratory conditions with over 2,000 samples. It scored highest in accuracy, precision, and mouth alcohol detection compared to competitors like the Evidenzer 240 Mobile and Datamaster DMT-GF. Yet, even this top-rated instrument can be affected by foreign objects in the mouth, as detailed in the report's laboratory evaluation appendix.
How Chewing Gum Introduces Mouth Alcohol and Compromises Results
Chewing gum, especially sugar-free varieties, often contains sugar alcohols like sorbitol, xylitol, or even trace ethanol in flavorings. When you chew, these compounds can dissolve and mix with saliva, mimicking the presence of alcohol in your mouth. If you blow into the Intoxilyzer 9000 shortly after, the machine may detect this as elevated BAC, even if you're stone sober.
The GBI evaluation specifically tested mouth alcohol detection with foreign objects, including gum. In one experiment dated March 6, 2012, researchers used Dentyne Ice Arctic Chill gum (1 piece) combined with an ethanol source (Binaca Fast Blast Cool Mint spray, 3 squirts) to simulate residual mouth alcohol. The results, shown in the chart below from page 107 of the report, illustrate how the Intoxilyzer 9000 registered numerical BAC readings that dissipated over time, while competitors flagged "MA" (Mouth Alcohol) more persistently:
| Sample | Time Elapsed (min) | Intoxilyzer 9000 | Evidenzer 240 Mobile | DMT-GF |
|---|---|---|---|---|
| Dentyne Ice Arctic Chill - 1 piece | Baseline | 0.000 | 0.000 | 0.000 |
| 0 | MA | MA | MA | |
| 2 | 0.049 | MA | MA | |
| 3 | MA | |||
| 4 | 0.020 | MA | ||
| 6 | 0.000 | 0.000 | MA | |
| 9 | 0.000 |
(Note: "MA" indicates Mouth Alcohol detected; blank cells mean no test at that interval. Thermometers used: 72576029, 11564016.)
This data shows that with gum in the mouth, the Intoxilyzer 9000 detected a reading as high as 0.049 at 2 minutes post-exposure, dropping to 0.020 at 4 minutes, and clearing to 0.000 by 6 minutes. In contrast, other devices flagged MA longer, but the key takeaway is that gum can cause temporary inflated readings on the 9000 if testing occurs too soon. We've heard from clients in Gwinnett County who chewed gum to freshen up after a meal, only to face skewed results during a traffic stop.
Worse yet, if you're chewing during or right before the test, it could trap alcohol vapors from earlier drinks, amplifying the mouth alcohol effect. Dental appliances or even vomiting prior can compound this, but gum is a common culprit officers might overlook. The result? A reading that suggests impairment when there might be none, turning a routine stop into a full-blown DUI arrest.
Georgia's Protocols: The 20-Minute Rule and Why It Matters
To combat issues like mouth alcohol, Georgia law mandates a 20-minute "deprivation period" before administering the Intoxilyzer 9000 test. During this time, officers must observe you to ensure nothing enters your mouth—no food, drink, gum, or tobacco—and that you don't burp, regurgitate, or do anything that could introduce contaminants. This waiting period allows residual mouth alcohol to clear naturally, as evidenced by the GBI tests where readings normalized within minutes.
But here's the catch: If the officer skips or shortens this period, or fails to check for and remove gum, the test results can be invalid. In Gwinnett County, where DUI enforcement is strict, procedural lapses like this happen more often than you'd think. The GBI evaluation emphasized the 9000's excellent mouth alcohol detection, but it still relies on proper operation. We've successfully challenged breath tests in court by proving protocol violations, such as testing too soon after gum was chewed, leading to dismissed charges or reduced penalties.
Challenging Compromised Breath Test Results in Court
If chewing gum played a role in your elevated reading, it could be grounds for suppression of evidence after a Daubert hearing or a hearing on the reliability of the scientific or technical evidence Georgia courts recognize that breath tests aren't infallible, and factors like mouth alcohol can lead to unreliable results, as supported by the GBI's own findings. A skilled DUI attorney can:
- Review dashcam or bodycam footage for protocol errors.
- Bring in expert witnesses on breathalyzer science to explain mouth alcohol interference, referencing evaluation data like the foreign object chart.
- Argue that the Intoxilyzer 9000, while advanced, still succumbs to human error or device limitations.
Final Thoughts: Don't Let a Faulty Test Define Your Future
Chewing gum might seem harmless, but in the context of a Gwinnett County DUI stop, it can seriously compromise Intoxilyzer 9000 results by introducing mouth alcohol and inflating BAC readings, as demonstrated in the GBI's comprehensive evaluation. While myths abound about "beating" the test with gum (spoiler: it often backfires), the real issue is how these interferences highlight the flaws in breath testing.
If you're facing DUI charges and suspect your breath test was skewed—whether from gum, mouthwash, or other factors—time is critical.
Contact our Gwinnett County DUI experts today for a free consultation. We know Georgia's laws inside out and can help protect your rights, license, and freedom. Remember, a positive test isn't the end of the road; it's often just the beginning of a strong defense. Stay safe out there!
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