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Litigation Blog.
The seasoned lawyers and litigators at The Rubinstein Law Firm are here to share their insights with you.

Are breath test device readings always accurate?

A conviction for operating while intoxicated in Michigan means serious consequences, some of which might include hundreds of dollars in fines, time behind bars and more. When a Michigan law enforcement official pulls you over and asks you to take a breath test, a whole lot rides on the results of that test. However, breath test devices are not immune to error, and there are certain factors and circumstances that have the potential to make the readings they produce inaccurate.

According to BACtrack, when testing for blood alcohol content, blood tests are more accurate than breath tests. However, they are harder to administer. Thus, many law enforcement agencies rely on breath test devices during most of the traffic stops where they suspect a driver is under the influence. However, the following factors have the capacity to offset the accuracy of a breath test device.

Poor calibration or lack of calibration

When it comes to breath test readings, precision matters. Breath test devices are highly sensitive, and those who use them to determine a driver’s level of intoxication must calibrate them regularly. When a breath test device does not undergo proper calibration, the results it produces may be unreliable.

Substances in the mouth

Certain over-the-counter products that contain alcohol, among them certain mouthwashes and breath fresheners, have produced false-positive breath test device results. Certain types of medication may also cause it to appear like you had ingested alcohol when you had not.

Environmental factors, human errors and device software glitches are among the other variables that have the potential to lead to a false-positive breath test result.