Personal Attention.
Aggressive Defense.

Photo of Thomas C. Mooney

Breathalyzer results may be unreliable

On Behalf of | Nov 5, 2019 | Criminal Defense

Maryland prosecutors often rely on Breathalyzer tests to convict people accused of drunk driving. However, a report from The New York Times highlights the challenges of such tests as well as their questionable accuracy. While the science underlying a breath test for blood alcohol concentration may be fundamentally valid, those scientific conditions are often not replicated in the roadside and even police station breath tests administered to people accused of driving under the influence. The report noted that in several states, judges have thrown over 30,000 Breathalyzer test results out of court due to their unreliability.

Some of the major problems with breath test machines include poor maintenance, human error and inaccurate calibration. In most cases, the machines were originally programmed correctly, although this may not be the case for older models that are no longer on the market. Some states may not update their lists of acceptable devices to remove old ones, despite the heavy penalties that can accompany a drunk driving conviction. For example, some types of Breathalyzers produce false readings if the person taking a test has had a breath mint. In other cases, the machine is simply too old and no longer functions properly.

This is especially likely if the machine was not professionally calibrated and repaired regularly. The newspaper’s investigation found that some police departments developed their own chemical solutions for cleaning the devices rather than using a specialized substance from the manufacturer. One agency drilled a hole in a machine because it believed it produced results that were too low.

The consequences of these kinds of errors can be significant. A DUI conviction can lead to jail time, high fines or the loss of a driver’s license. People facing DUI charges can consult with a criminal defense attorney about their options to contest the allegations.