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Are Breath-Alcohol Test Accurate Under Minnesota’s Drunk Driving Laws?

If you’ve had the misfortune to be pulled over for a suspected drunk driving offense, you know that one of the first testing methods is a field test called a breath-analyzer. Most people consider this test as a conclusive proof – either you test above the legal limits or not. But what if this test isn’t accurate? It’s an important question to consider, especially if it results in a felony DUI MN conviction.

First, you need to understand that the breath analysis is based on a ratio between alcohol exhaled in breath and the amount alcohol in blood levels.  The breath analysis machine’s design is based on this ratio, which is 1 to 2100. But in actuality, the true ration for an individual can vary from 1:1300 to 1:3000.

Breath Analysis for DWI in Minnesota

Breath analysis sounds like an accurate means of establishing whether someone is driving under the influence. But in actuality, this test, especially when performed in the field (road-side) is fraught with errors. Breath-analyzers can be inaccurate as a result of human errors, internal machinery malfunction, interference, or maintenance problems.

The police officer that administers the field test is considered responsible for the test. He or she should advise suspects that they have the option of refusing to take the test in the field. Too often, this information is not adequately communicated by the officer. This is frightening to consider, especially when felony DUI MN convictions can result from these tests.

Some of the breath-analysis machines use an infrared system to measure alcohol levels. When the breath samples are blown into the machinery chamber, the infrared beam shoots from one end of the chamber to the other. The infrared beam will be absorbed by alcohol molecules. The more light that is absorbed from one side of the machine to the other indicates a higher reading of alcohol levels.

Unfortunately, the beam may be affected by alcohol that is present in the mouth (as opposed to in the actual blood and breath), other molecules that have the same spectrum as alcohol, or even interference from nearby radar systems. Hardly a conclusive process but something that is consistently used to enforce Minnesota’s drunk driving laws.

What’s important to realize is that you have options, especially when it comes to arguing and defending yourself against Minnesota drunk driving laws and arrests. An experienced attorney understands the potential for testing errors and will help you vigorously defend yourself against these charges.