A Miscalibrated Breathalyzer Can Result in Your Case Being Dropped

A Miscalibrated Breathalyzer Can Result in Your Case Being Dropped

Drunk driving cases generally hinge on two things—Breathalyzer test results and officer testimony regarding whether the driver appeared to be intoxicated. The problem with the second part is that police always cite the same factors they learn at the police academy in claiming in their report that a driver is intoxicated—slurred speech, bloodshot eyes, impaired reactions, erratic driving, and all the other possible signs of intoxication taught in training.

The problem is, not all drivers pulled for DUI actually exhibit these symptoms, nor are they all pulled because of erratic driving. Many, if not most, are pulled for speeding, at which point the officer may claim to smell alcohol. Further, the officer may cite signs of intoxication even if the driver refuses to take field tests, speak, or otherwise submit to tests that would support those kinds of conclusions by the officer. In short, without further evidence, many marginal DUI cases are really a matter of he said-she said.

This conflict can result in cases such as a 2005 DUI arrest in Washington, D.C., where the female driver had a single glass of wine at dinner, tested with a blood alcohol content of 0.03, but nonetheless was charged with DUI because, basically, the officer said so. (The national standard for presumption of being under the influence is over 0.08, and the presumption of not being under the influence is under 0.05.) The case ultimately was tossed out. But what happens if a Breathalyzer test supports the officer’s decision to arrest a driver for DUI? That could depend on whether the Breathalyzer was properly calibrated.

What Is Breathalyzer Calibration?

Breathalyzers are used to measure the amount of alcohol in a person’s breath, based on parts per million. They use a ratio of the amount of alcohol in breath to determine how much alcohol is in a person’s blood, thereby giving the blood alcohol content ratio used to determine whether a driver has a blood alcohol content at or above the 0.08 percent that supports a per se DUI charge. Setting aside the problems in determining the breath-blood alcohol ratio, Breathalyzers must be accurately calibrated to make this determination. Just as an improperly calibrated speedometer won’t tell you your actual speed, the same is true for an improperly calibrated Breathalyzer.

Improper calibration can take different forms: improper performance of the calibration, including not calibrating frequently enough, or simply not calibrating the device. The California, D.C., and New Jersey cases, all three improper methods of calibration occurred. In general, standards show that Breathalyzers should be calibrated about once a month.

For the two Breathalyzer devices with results admissible in court, the state requires calibration only every 62 days, about twice the interval generally accepted as adequate for proper calibration. While you are unlikely to get a Breathalyzer test dismissed if it satisfies state calibration requirements, multiple cases across the country make it plain that those calibration requirements often are not met, no matter what the particular requirements are.

Even when proper calibration intervals are satisfied, a Breathalyzer also could be improperly calibrated through failure to follow proper calibration or maintenance procedures. Because the device measures minute amounts of alcohol in your breath—the accepted ratio is 2,100 parts per million of alcohol in breath is equal to one part per million in the bloodstream—small errors or variations can create significant errors in results. Small discrepancies can have huge results in a procedure where such precision is required.

Bad DUI Test Results Can’t Support Bad Arrest Decisions

The outcome of DUI arrests frequently rests on the results of blood-alcohol-content breath tests—commonly known as Breathalyzer tests—that are intended to determine what a person’s blood alcohol content is at the time of arrest. Most field Breathalyzer tests are not considered admissible as evidence, so the vast majority of Breathalyzer test results used in court are from large, non-portable machines, which are used to perform breath tests at the police station, not in the field.

If Breathalyzer machines are not properly calibrated, the results are essentially useless. In November 2018, the New Jersey Supreme Court found that people could challenge more than 20,000 DUI convictions in that state because the Breathalyzer calibration records were false. The test results were ruled inadmissible, putting local law enforcement officials on the spot as to whether they should attempt to retry those cases without Breathalyzer test results. The defendants in those cases are free to challenge their convictions. While that doesn’t mean they will win—there could be other, compelling evidence in favor of conviction—it certainly increases their chances.

Similarly, nearly 400 DUI convictions in the District of Columbia since 2008 were thrown into question in June 2010 when it became known that all of the Breathalyzer machines used by D.C. police were improperly calibrated. While people only challenged 50 of those 400 convictions in court, the District wound up paying roughly $400,000 in settlement payments for some of those challenges. One county in California dismissed dozens of DUI cases because of Breathalyzer calibration problems, and San Francisco determined that roughly 1,000 DUI convictions were in danger of being dismissed because of improperly maintained and calibrated Breathalyzers.

While an improperly calibrated Breathalyzer will not automatically result in the dismissal of a DUI case, it can go a long way toward helping your lawyer earn an acquittal. When a major portion of the prosecution’s case has a significant flaw, that has a tendency to bring other aspects of the case into doubt. If the police aren’t even maintaining their Breathalyzers properly, what else are they doing wrong? While it isn’t automatic, dismissal for an improperly maintained Breathalyzer becomes much more likely.

If You Need Representation on Drunk Driving-Related Charges in DuPage, Kane, or Cook County, Contact the Criminal Defense Attorneys of Martin & Kent, L.L.C.

If you are facing drunk-driving charges, a strong defense is imperative. The potential for jail time, negative employment impacts, and all the other consequences of a DUI conviction virtually mandate that you find the best defense possible. Call the criminal attorneys of Martin & Kent, L.L.C. With decades of combined experience, including years as felony prosecutors, we have the inside knowledge and experience to put forward an aggressive defense for you. For a consultation in DuPage, Kane, or Cook County, contact us 24 hours a day at (630) 474-8000.



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