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How Breathalyzers Have Influenced OUI Laws Across the Country

A man blowing into a breathlyzer inside of a car, representing how one can benefit from calling a Maine criminal defense lawyer.

In a recent blog post, we delved into the history of the breathalyzer, one of the biggest developments in the history of the enforcement of operating under the influence (OUI) laws. In fact, the breathalyzer has been so important that it has even changed OUI laws in Maine and elsewhere, despite its unreliability.

Early OUI Enforcement

The first OUI law was passed in New Jersey in 1906, but enforcing it was tricky: People were aware that you could have trace amounts of alcohol in your blood after drinking, but there was no practical and safe way for police to draw blood during a traffic stop. This meant police had to rely on the testimony of the arresting officers or witnesses to “prove” that an OUI defendant was driving drunk. Of course, this testimony was inherently unreliable, as it’s widely known that different people act differently when they’re drunk, making it almost impossible for officers and random bystanders to know for sure if someone – who they’ve only seen for a matter of minutes – was under the influence at a given time. Additionally, signs of inebriation could also be blamed on numerous other factors, like a driver’s nervousness or their physical abilities.

The unreliability of this law enforcement technique, however, wasn’t considered a major problem: Cars moved slowly before 1920, and then Prohibition made alcohol a crime from 1920 until 1933, so drunk driving was not considered a serious social issue.

OUI Laws Changed to Adopt Breath Testing

In 1926, scientists discovered that alcohol could be detected on a suspect’s breath as well as in his or her blood, and ten years later the first breathalyzer, the Drunkometer, was invented. The Drunkometer, however, seems to have been woefully unreliable: Numerous cases from the period that it was in use involve drivers with an absurdly high blood alcohol content (BAC) of around 0.4%. Further developments in breath testing machines led to the Breathalyzer, which was widely used starting in the 1950s, but inaccuracies and technical problems remained.

However, the presence of breathalyzers like the Drunkometer and the Breathalyzer showed that scientific-sounding evidence was possible to get in an OUI case. Lawmakers took this idea and ran with it, despite early disagreements in the medical community over what BAC level should be considered “impairing” for drivers. Indiana was the first to include a BAC limit in its OUI law as early as 1939. Other states followed suit, making a driver with a BAC of 0.15% or higher presumptively under the influence, and therefore guilty under their state’s OUI law. The standard was subsequently lowered by states to 0.10% in the 1980s, which then made it per se illegal to drive over this limit before lowering them again to the current standard of 0.08%.

OUI-Defense Attorneys in Maine

The influence that breath testing machines have had on OUI law in the United States cannot be overstated. Unfortunately, these machines are still far from accurate, so having a skilled OUI-defense attorney at your side is crucial if you’ve been charged with OUI. Call the Maine Criminal Defense Group Office at (207) 571-8146 or contact attorney William T. Bly online for the legal help you need.


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