You certainly want to avoid being charged with a driving while impaired (DWI) offense, so you probably try hard to keep your blood alcohol concentration (BAC) below the legal limit. This limit in Texas is set at 0.08% for most motorists. You know that it’s probably fine to have one or even two drinks before hitting this level, simply based on BAC charts that consider things like gender and weight.
But you shouldn’t trust those charts blindly. What if you buy your own breath test? Could this help you avoid getting a DWI because you can check your BAC on your own?
A personal test could prevent a drunk driving arrest
Where a personal breath test can help is that it may keep you from being arrested in the first place. If you take the test and you’re over the legal limit, you’ll know that it is unsafe for you to drive. It could be a false positive, of course, but it is better to err on the side of caution. You can also take the test repeatedly to see if you get similar results every time. In this way, a breath test can act as a warning device to let you know that it would not be wise to get in the car yet.
Personal test results cannot be used in court
Where a personal breath test will not help you, however, is if you have already been arrested. Evidence from an unofficial test is inadmissible in court. If the police give you a breath test that shows you are over the legal limit, for instance, the court will not be swayed by your own claim that your personal breath test produced a different result.
The reason for this is that courts only approve certain makes and models, and all procedures have to be followed by police officers. This includes things like calibrating breath tests. Additionally, a test that you administered to yourself could have been administered improperly or tampered with. In short, its results are not readily provable.
For all of these reasons, the results of a personal breath test cannot be used as evidence in support of your case. However, this does not mean that all hope is lost. If you are facing charges, it is wise to work with an experienced criminal defense attorney to assess the alternative defense options that you have at your disposal.