Most Americans are familiar with the idea that they are innocent until proven guilty, regardless of what criminal charges the state might bring against them. However, when it comes to drunk driving or DUI charges, it seems that more often than not there is a presumption of guilt rather than innocence for the persons accused.
This attitude likely stems from the fact that most drunk driving arrests result from an interaction with police that involves chemical breath testing. Many people have mistakenly come to view breath tests as a kind of science that conclusively shows the guilt of someone accused of an impaired driving offense.
Despite how much people seem to trusts these tests, research is making it increasingly clear that they aren’t as infallible as people think they are.
Chemical testing units are subject to many potential issues
Chemical breath tests work by detecting certain compounds in the air exhaled by the person undergoing the test. Even in a situation where the testing unit functioned properly and the human performing the test did so perfectly, the potential exists for a false positive due to other compounds potentially making the test believe alcohol was present. There are quite a few ways in which these tests can provide inaccurate results.
Human error is always an issue with any kind of testing
In theory, chemical breath tests have design features that make them user-friendly, allowing for their quick and efficient utilization in field situations, such as during a traffic stop. Unfortunately, despite their simple design, the person administering the test can still make mistakes.
They can make a mistake in how they perform a test, as well as how they read the unit. In some cases, officers haven’t had up-to-date training about the unit they use. Other times, the device itself can be a source of potential issues.
Breath test units require calibration and maintenance
Like any complex piece of equipment, a chemical breath test unit requires maintenance, frequent inspections, repairs as necessary and even calibration to ensure that it produces accurate results. With more modern devices, up-to-date software is also often critical to the performance of the breath test unit.
When the individual officer or their department fails to properly maintain, calibrate and inspect breath test units, the risk increases for inaccurate results that could leave someone vulnerable to criminal charges even though they didn’t break the law.