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

How reliable are breathalyzer results?

The results of “breathalyzer” alcohol tests are often portrayed as indisputable – the final word for all drunk driving accusations. Breathalyzer accuracy is important because a conviction of operating while intoxicated (OWI) charges can have serious repercussions, even for first-time offenders.

So, what would happen if we discovered there were potentially serious flaws with breathalyzer devices used right here in Michigan? It’s a situation that has been playing out recently.

Serious problems in Michigan

In January 2020, Michigan State Police revealed it had stopped using 203 breathalyzer machines after discovering issues with how they were calibrated, tested and maintained. These issues resulted in possible testing errors, meaning the results of dozens of drunk driving cases were suddenly in question. The department said it planned to re-certify, re-calibrate and verify the devices.

By February, state police had returned these breathalyzer devices to service, without offering much explanation as to what was fixed.

Widespread issues with breathalyzers

This story from the Michigan State Police is concerning, but it may be the tip of the iceberg. As a New York Times investigation recently found, breathalyzer machines across the U.S. are often “unreliable,” pumping out skewed results. These errors mean individuals facing drunk-driving charges based on a breathalyzer reading may, in fact, have had a much different blood-alcohol content than what was displayed.

Breathalyzers are sensitive machines. They must be maintained, calibrated and cared for in very specific ways. A faulty machine should not result in a conviction and all the consequences that come with it.