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Breathalyzer Accuracy


DUI lawyers have to deal with breathalyzers often. As When you are arrested while drunk driving and charged with DUI, the cops will ask for BAC (blood alcohol content). BAC is usually taken through one of the three chemical methods, i.e. urine, blood, or breath. The accuracy of the test depends on how precisely the test is being conducted. It’s important to understand that breathalyzers may provide false readings. There are different factors involved; it could be the difference between having the charges dismissed and spending time behind bars. However, DUI lawyers known best for criminal defense can assist you in getting through DUI cases. According to NHTSA, about 28 people in America die in drunk-driving car crashes each day.

In this blog, we’ll be discussing some factors that could jeopardize your breathalyzer tests and thus become a shred of weak evidence against you.

Impact of Alcohol on Breathalyzers:

You probably don’t feel the effects of the alcohol right after finishing a drink. However, the smell and taste of alcohol remain in your mouth for quite a while before the drink starts affecting your consciousness. This alcohol might impact your breathalyzer results. When an officer asks you to blow into the machine, the breath that enters the machine will pick up bits of the alcohol that remained in your mouth, increasing the concentration that ultimately increases the chances of the BAC limit, i.e., less than .08%. Nonetheless, your result isn’t accurate because this alcohol has not affected your system, which is why officers usually have to wait at least half an hour after arresting and testing someone; but they don’t always do that.

Improper Machine Calibration:

A breathalyzer test needs to be correctly calibrated to work properly. If the machine hasn’t been regulated in a prolonged period, or the specialist who calibrated the machine made a mistake in doing so, then the results may differ. Even a minor human or technical error can make the difference between your sample passing as legal and blowing over the limit, and consequently, you have to face a DUI charge. Normally, your DUI Lawyers will request the calibration records of any breathalyzer machine as soon as possible to look for contradictions they use to make your defense strong.

Human Error While Operating Breathalyzer Machine:

Although breathalyzer machines are quite easy to use, you still need to have a qualified and knowledgeable person conduct the test to ensure the accuracy of the results. If the person performing the test makes an error or lets the test be conducted in a way protocol is not being followed, the results will be inaccurate and doubtful. Even though everything is computerized and has specialized software, someone still needs to work more attentively.

Bad Sampling:

Like blood and breath tests, the only best way to get an accurate reading is to take multiple samples. One sample could be infected somehow, or another may have been wrongly collected. Therefore, officers should take multiple readings to gain a better sample size and be more assertive with the results. A single sample could never be efficient for BAC, leading to a false positive. However, some other contributing factors may include:

  • Breathing rate
  • Body temperature
  • Certain prescription medications
  • Hypoglycemia
  • Low-carb diets
  • Exposure to chemicals
  • Vomiting
  • Burping
  • Acid reflux

How Can a DUI Attorney Help?

A failed Breathalyzer test does not certainly mean a prosecutor has a winning case against you. You should hire an experienced DUI attorney so that he can help you challenge the results of the Breathalyzer test. Your attorney should have more than 30 years of experience successfully defending his clients facing DUI charges and inaccurate BAC results. A knowledgeable lawyer may discredit an improperly collected breath test and get the results discarded in court. The police officer could probably dismiss a DUI charge without this vital evidence.

Can DUI Lawyers Challenge Breathalyzer Results?

It is not easy to challenge the accuracy of a breathalyzer test, especially if the results were considerably higher than the 0.08% legal blood alcohol limit. But if you blow just to some extent over the legal BAC limit, your attorney can make an argument that your results are inaccurate, and your case could be closed. The best way to determine whether your breathalyzer results should be challenged is to discuss your case for free with experienced DUI Lawyers at our law firm. You can trust our skilled and resourceful attorneys who will assist you in building your strongest defense.