Can Breathalyzer tests fail?

 Posted on August 15, 2017 in DUI/OWI

When individuals are slapped with a drunk driving charge, prosecutors rely on certain tests to try to prove their case. While field sobriety tests and breath tests are considered reliable evidence that a driver is under the influence of alcohol, motorists in Wisconsin should note that these tests and devices are not always accurate and reliable. Thus, it is possible to challenge these results, helping an accused individual assert a strong defense.

Can Breathalyzer tests fail? While these tests are the backbone of drunk driving campaigns and are heavily relied on by law enforcement to determine if the blood alcohol content of a driver is intoxicated, these tests are prone to errors and mistakes.

The process of collecting a breath sample and analyzing it might seem scientific, allowing for an equitable and fair result, but, this is not always the case. It is not scientific and it does not rely on any existing or accepted science. Because there is a wide variation of results form person-to-person, it is tough to say that this test can fairly assess whether a person is actually impaired.

The best way to measure blood alcohol content is by conducting a blood test. This is generally an accepted and accurate indicator of impairment. According to current studies, when comparing the estimates of a BAC by a breath test to the actual BAC determined by a blood test, the margin of error is around 50 percent. This means, for example, if a Breathalyzer test reads 0.1 percent, the actual BAC level lands somewhere between .05 and .15 percent.

The lack of precision with a breath test is enough for a motorist accused of a DUI to consider challenging the test to which he or she was subjected. Taking this step and asserting a strong defense could help a defendant obtain reduced or dismissed charges, thereby allowing him or her to avoid harsh penalties.

Source: National Motorists Association, "Breathalyzers Fail Legitimacy Test," accessed August 5, 2017