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How reliable are breathalyzers?

| Jun 3, 2020 | Criminal Defense |

Even if it’s your first offense, driving while intoxicated comes with some sobering consequences in Virginia. In addition to a criminal record, drunk drivers will likely face hundreds of dollars in fines, license revocation for 12 months and an ignition interlock device.

Alcohol breath tests, or breathalyzers, are fundamental tools in the criminal justice system for determining whether a person is driving over the legal limit. Field sobriety tests or blood samples may also be performed, but generally, it’s the results of the breathalyzer test that seals the driver’s fate.

Those with a blood alcohol concentration (BAC) of 0.08 or higher will almost certainly face an arrest. But what if the results are wrong? A 2019 investigation by the New York Times found breathalyzers may not be as reliable as you’d hope.

Skewed results not as rare as you’d think

According to the article, even though most breathalyzers are marketed to be precise to the third decimal, they generate skewed results with concerning frequency. In just one year, Massachusetts and New Jersey threw out 30,000 breath tests in just 12 months due to human errors or lax government oversight.

What causes inaccurate breathalyzer results? The investigation found a multitude of reasons spanning across the country, including:

  • Some police departments fail to calibrate the devices properly.
  • Serious programming errors and technical shortcomings in the machines.
  • Some police departments used home-brewed chemicals to calibrate the instruments.
  • Breath test manufacturers refuse to share their software with the public.
  • There is no national standard for the devices law enforcement use.
  • Altered results from toothpaste, mouthwash, hand sanitizer and other products.

The bottom line

Breathalyzers help to keep the roads safer, but unreliable results could also put innocent people behind bars. While it may be tempting to refuse a breath test when pulled over to avoid inaccurate results, it will result in license revocation for a year. Ultimately, the best way to avoid a DUI charge on your record is not to drink and drive.