When a police officer pulls you over and suspects that you have had too much to drink, they will take certain steps to help prove their suspicions. They need probable cause and then evidence that can hold up in court.
They will ask you questions about your behavior before your traffic stop. They may also have you exit the vehicle and perform a field sobriety test. At that point, if the officer has probable cause to suspect alcohol intoxication, they can then ask you to perform a chemical breath test, sometimes called a Breathalyzer test.
How breath tests work
Breath testing collects a sample of exhaled air and looks at the concentration of a certain kind of molecule within that gas sample. Using that information, the device then produces a blood alcohol concentration (BAC) reading.
Any results above 0.08% will be enough to trigger an automatic arrest and drunk driving charges. Sometimes, people facing drunk driving charges can challenge those test results.
Chemical breath testing is susceptible to many kinds of problems
Chemical breath tests can easily produce inaccurate results, and drivers are the ones who pay the price for those issues. Any device that performs calculations based on chemical samples requires regular calibration. Without proper maintenance, the device could easily show a higher BAC than it should.
Police officers who administer chemical breath tests should have up-to-date training on the use of the devices. Their departments should also have thorough records about the calibration, maintenance and software upgrades necessary for the proper performance of their devices.
Reviewing internal records about the officer’s training or the device’s maintenance can sometimes give you a good idea about how to defend yourself.
Chemical breath tests often don’t hold up in court
Even if you can’t find a glaring issue with how the officer performed the test or maintained the device, you could still challenge test results that you know are inaccurate. Anything from medical issues to dietary changes could affect the results of a chemical breath test.
Calling the science into question can be a sound strategy for those who know that the breath test results don’t accurately reflect their BAC at the time of the traffic stop. Learning more about how the state builds a case around drunk driving charges can help you decide how to defend yourself.