Administering a Breath Test in a Manassas DUI Case

When a person is charged with a DUI in Manassas, the result of their breath test is often a key element of the prosecution against them. For this reason, it is important to understand how the test is supposed to be administered and the legal weight it may hold in court. To learn more or discuss your case, call and schedule a consultation today.

Taking a Breath Test

The breath test is administered at the police station subsequent to arrest. Before the test can be given, there is a waiting period of at least 20 minutes where the individual has to be observed and where it must be confirmed that they have not introduced alcohol back into their mouth either by burping or vomiting.

Once that period has been completed, there is an implied consent statement that is read to the defendant letting them know that they may refuse to take the breath test, but that there will be a consequence to that, which is being charged with refusal.

The individual is then brought to the machine and after the officer has swiped their card to begin the process, the defendant will be asked to blow into the machine until there are at least two good samples that are received.

Once there are two good samples received, the machine will print out a document, which contains the blood alcohol level of the individual.

How the Machines Work

The machine that administers the breath test measures the amount of alcohol that is expelled from the lungs during respiration. When an individual ingests alcohol, their body metabolizes that alcohol over time and eliminates some of it through the respiratory system. The amount of that byproduct that is found in the individual’s breath can be correlated to the amount of alcohol that is present in their bloodstream.

The machine tests that level and then gives a result as to what the actual blood alcohol is.

Elements of a Valid Sample

For there to be a valid sample, there have to be two good blows. What that is going to mean is that an individual is able to expel enough air from their lungs for a long enough period of time for the machine to take a good reading on two different occasions.

A breath test machine has to be regularly calibrated. The internal mechanism of the machine actually contains a program that will cause the machine to self-calibrate once before each test is taken and then once after each test is taken. In addition to this, there is maintenance and calibration that must take place at regular intervals for the breath test to be valid and usable in court.

Officer Procedure

In order for a breath test to be valid, the police first have to observe the individual for at least 20 minutes to confirm that they do not have any alcohol present in their mouth. In addition to that, there has to be implied consent, which is a statement that is read to the defendant before the test is given.

Another thing that has to be done for the test to be valid is that it must be taken no later than three hours from the time that the arrest occurred.

Benefit of a Manassas DUI Attorney

There are a number of ways to challenge the results of a breathalyzer test. Most of them are highly technical and many of them require the involvement of an expert to successfully mount them at trial.

This is a very complicated and hyper-technical area of the law. For that reason, a person should only work with an experienced attorney whose focus is on DUI to give themselves the best chance to detect any errors in the process that have occurred relative to the breath test that has been taken.