Preliminary Breath Test in Virginia

There are two types of breath tests that may be involved in a Virginia drunk driving case. This includes the preliminary breath test and the official breath test taken at the police station or jail. The preliminary breath test, also known as a breathalyzer or roadside breath test, is not mandatory. In most cases, a preliminary breath analysis can only hurt, not help, your DUI case.

Roadside Breath Test in Virginia DUIs

Roadside breath tests are used to help the police gather enough evidence to justify making an arrest. For example, if a driver was weaving or driving recklessly but does not smell like alcohol, the officer may be concerned that the driver is under the influence of alcohol, but does not have sufficient evidence to arrest the driver for DUI. However, if the officer asks, and the driver submits to, a preliminary breathalyzer test which shows alcohol in the driver's body, he may have sufficient cause to make a drunk driving arrest.

Preliminary breath analysis is often used with field sobriety tests (FSTs) to help law enforcement evaluate whether a driver may be impaired. However, preliminary breath tests (and field sobriety tests) are highly subjective and do not always provide a correct analysis of the driver's impairment or accurate blood alcohol level.

The results from these roadside breath tests, prior to arrest, are not used as evidence against the driver in court to determine whether the driver is guilty of a DUI. Instead, an official breath or blood test taken after a DUI arrest is used as evidence. One of the reasons the preliminary breath tests are not used for evidence is because they are not as accurate and can provide a false positive result for drivers who are not over the limit.

Can I Refuse a Preliminary Breath Test?

You can refuse a preliminary breath test in Virginia. Drivers are not required to give preliminary roadside breath tests in Virginia. There are no automatic consequences or penalties for refusing a roadside breath test, in the sense that the results cannot be used against the driver to prove guilt at a trial.

Under Code of Virginia § 18.2-267(C), any person suspected of driving under the influence shall have the right to refuse to permit his breath to be preliminarily analyzed and failure to permit such an analysis shall not be evidence in any prosecution for a drunk driving offense.

How the Roadside Breath Test Works

Roadside breathalyzers test the breath sample given by the driver. If the driver has consumed alcohol, that alcohol is absorbed by the body and is present in other organs, including the lungs. The preliminary breath test device analyzes the breath sample to estimate how much alcohol is in the individual's body based on the amount in their breath.

Problems with Preliminary Breathalyzer Tests

Preliminary breath tests are handheld devices that give an estimated analysis of a driver's BAC. There are a number of factors that can cause a preliminary alcohol screening device to give a faulty result. This includes:

  • Improper maintenance,
  • Failure to calibrate the device,
  • Damage to the device, or
  • Failing to properly clean the breathalyzer.

The use and maintenance of the preliminary breath test device must comply, in part, with the following sections of the Virginia Administrative Code:

6 VAC 40-20-170. Preliminary breath test device.

6 VAC 40-20-190. Operational procedures.

6 VAC 40-20-200. Preventive maintenance.

Preliminary Breath Tests and Probable Cause 

Although results of a PBT cannot be used “in any prosecution,” for DUI, the results can be admitted into evidence in a probable cause or suppression hearing. Courts have held that ‘[P]rosecution' as contemplated in this statute is limited to the proceedings devoted to ‘determining the guilt or innocence of a person charged with a crime.' Stacy v. Com., 22 Va. App. 417, 423, 470 S.E.2d 584, 587 (1996).

Breath Test After a Virginia DUI Arrest

There is a different type of breath test that comes after a Virginia DUI arrest. This is the official breath test which is generally completed at the jail or magistrate's office. Unlike the roadside breath test, the official breath test is taken after an arrest and can be used as evidence against the driver in the criminal case.

Refusing a chemical test (breath or blood) after a DUI arrest comes with consequences. Pursuant to Code § 18.2-268.3 refusing a breath test after a DUI arrest will result in an automatic driver's license suspension for one year. A second refusal may be considered a misdemeanor offense and could result in a suspended license for three years.

Ignition Interlock Breath Testing

If the driver is convicted of a DUI, pursuant to Code § 18.2-270.1, the court may require an ignition interlock device (IID) to be installed to allow the driver to get their license back. This is a type of breathalyzer that connects to the vehicle's ignition. The breathalyzer analyzes the driver's blood alcohol content and will prevent the automobile from starting if the BAC reading on the device is greater than .02%.

Charlottesville DUI Defense Lawyer

It may not seem like a driver can refuse a roadside breath test. However, even when the driver does submit to a preliminary breath test, an experienced DUI defense attorney can challenge the accuracy of the test and the reason for making the initial traffic stop. If you were arrested for drunk driving in Virginia, talk to an attorney with a record of successfully defending clients facing DUI charges. Contact attorney me today for a free consultation.

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