Photo of policeman and accident perpetrator during a breathalyzer test

Breathalyzers are a standard device used by police officers to determine the blood alcohol content in a driver’s body. Generally, the BAC limit in one’s body should be less than 0.08%. Remember when we talked about some of the DUI crime lab errors? These devices are prone to erroneous results that could land you in jail for a DUI without an attorney who knows the ins and outs of breathalyzer tests. On the upside, defendants can challenge results from the breath tests by considering a few factors at the time of the arrest.

1. Breathalyzers, in general, are not reliable. (Check out this video!)

Unlike the chemical blood test, the breathalyzer has one major weakness that leaves it vulnerable to false readings: the sample is collected indirectly into the device. As a result, this leaves it open to changes in the immediate environment, including changes in temperature, pressure, and chemical composition. Chemical sprays, fumes, and adhesives all have potent components that can interact with the device to form false positives. Unless the officer administers the test several times and in a different location to achieve a consistent set of results above the legal limit, we cannot assume that results from the device are correct.

2. The device was not properly calibrated.

Like many electronic gadgets used for chemical testing, calibration is necessary for maintaining the efficiency of the device. Devices need maintenance. Calibration ensures the devices function correctly regardless of frequency of use. To determine whether the device used at the scene was adequately maintained, a knowledgeable attorney would first ask to review the calibration records. From these records, the lawyer can establish whether the police department carried out routine maintenance and calibration.

3. The administering officer was not trained to conduct the exercise.

Administering a breathalyzer test seems relatively easy, and anyone with two hands and a brain can do it, correct? Unfortunately, only a trained officer knows how to correctly use the device since there are details to consider like how long to blow and correct placement. If your attorney can provide substantial evidence that the administering officer was ill-skilled, this improves your chances of evading a DUI conviction. 

4. The test was an illegal search.

Legally, officers are not allowed to administer tests randomly to any motorist. They must have probable cause or reasonably suspect that the driver was under the influence while driving the vehicle. The 4th amendment protects citizens from illegal searches and breathalyzer tests fall under this category. If an attorney can show that the officer had no probable cause to issue the arrest or conduct the test, the court is legally obliged to rule in your favor.

Knowing how to challenge a DUI breath tests makes a world of a difference between an efficient lawyer and one who simply has a license. Luckily, Attorney Don Hammond, Criminal Defense Hero, is the perfect attorney to visit if you have any doubts about the positive breathalyzer test results.

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