Breathalyzers in Virginia DUI Cases

Chances are if you are stopped and arrested for driving under the influence you will take some kind of breathalyzer test. With this in mind, the following is what you need to know and how reliable these tests are. For assistance building a strong defense or questioning the result of a breathalyzer, call and schedule a consultation with a Virginia DUI lawyer today.

Use of Breathalyzers in Virginia

Breathalyzers had been used in Virginia for many, many years and the trend is always towards more and more accurate machines. Over time, various machines that have been used in the past have been shown, by defense lawyers in most cases, to be less accurate or less reliable than current technology.

This has frequently prompted localities and different police departments to use better and more modern machines. However, in many jurisdictions, they are still using older machines which are in some ways outdated. Having a familiarity with the different kinds of machines that are used and the different kinds of problems that arise with those machines can make a real difference in the right case.

Reliability of Breath Test Instruments

Breathalyzers are reliable instruments in Virginia as long as they are properly maintained and regularly tested. Every machine that is used for a breath test machine has sensitive detectors that have to be constantly calibrated. They’re so sensitive in fact that a sample test is done before and after every single test to insure accuracy.

The Department of Forensic Science actually maintains maintenance logs and calibration logs which an attorney can access which will show not only what care has been taken of the machine but will also show the details of the test of the accused to a much higher degree than what shows up on the certificate of analysis.  It will also show the results of other tests taken in the same time frame.

Common Misconceptions

Some of the common misconceptions about breathalyzers in Virginia are that you only have to give one breath sample in order for it to work. In most cases, there have to be at least two good breath samples that are given. The lower of the two is the one that is actually printed out on the certificate of analysis. Many people think that because they did not give a sufficient breath sample on one of the tests they took that the machine could not have given an accurate result. But the standard is there have to be two tests that are fully completed and then the lower of the two tests is the one that is used.

What Else Should People Know About Breathalyzers in VA?

The main thing to know about breathalyzers in Virginia is that during the course of a DUI stop, you absolutely going to encounter two of them. The first breath test is the one that is offered on the side of the road which is sometimes referred to as a preliminary breath test or a PBT. This is a test that is at least in theory supposed to help you clear yourself, but in reality, the PBT test is use to help develop probable cause for the arrest. In the course of a DUI stop it may not be preferable to take this test.