When a breathalyzer test measures your blood alcohol concentration (BAC) at .08 or higher, it may feel like the police have you dead to rights. However, remember that you’re innocent until proven guilty. In addition, recent studies have called into question the reliability of breathalyzer tests.

How accurate are breathalyzer readings?

Several factors can impact an individual’s BAC reading, including:

  • The amount of alcohol consumed
  • A person’s metabolism
  • Health issues

A blood test measures the amount of alcohol in your bloodstream. It’s pretty hard to skew the results of a blood test. A breath test, on the other hand, measures the amount of alcohol that is dissolved in a person’s exhaled breath. These readings could fluctuate from breath to breath. For example, if you happen to burp right before exhaling, it may cause your BAC reading to come back higher than it actually is. A breath test is more of an estimate of your BAC than a foolproof measurement.

In addition to fluctuating readings, breathalyzers can be wildly inaccurate if they aren’t correctly calibrated. One investigation found that improperly calibrated machines could result in BAC readings that were as much as 40% higher than a person’s actual BAC.

So, the results of my breathalyzer test don’t matter?

The law is not prepared to write off the results of a breathalyzer test. The results of a breath test can and will be used to support a charge of drunk driving. However, it can be easier to attack the reliability of these readings as part of your defense strategy.

Breath test reliability is only one factor that’s worth exploring. There may be other grounds for challenging your arrest. A skilled legal professional can help explore your options for fighting a drunk driving charge.