DUI Chemical Tests

Other than the police officer's testimony, chemical tests are typically the primary evidence used to convict a driver of a DUI in Virginia. Chemical tests of the driver's breath or blood can be used to show that there was a certain amount of alcohol and/or drugs in the driver's body shortly after an arrest for driving under the influence.

Refusing a chemical test can result in penalties even if the driver doesn't have any alcohol or drugs in their system. Your Virginia DUI defense attorney understands how to challenge chemical test evidence for the best chance to avoid a criminal conviction. If you are ever pulled over for a DUI, it is important to understand police DUI tests and the consequences of refusing a breath or blood test in Virginia.

Virginia DUI Chemical Tests

Chemical testing is used to show whether the driver had the presence of alcohol or drugs in their system. Alcohol testing also shows the approximate amount of alcohol in the body to determine whether the driver is over the legal limit for drunk driving. Breath testing is the most common test for DUIs in Virginia. However, law enforcement may also use blood tests, especially if the officer suspects the driver may be under the influence of drugs.

There are two types of chemical breath tests involved in a Virginia DUI. The legal implications relating to these breath tests are very different in Virginia. Pursuant to § 18.2-267, a driver is entitled to a roadside or preliminary breath test and the driver can refuse to submit to a roadside breathalyzer test. However, pursuant to § 18.2-268.2, by driving on the highways of the Commonwealth drivers in Virginia have “consented” to allowing a breath or blood test after a DUI arrest, provided the arrest was within 3 hours of the driving. Refusing a chemical test after the arrest will result in a mandatory license suspension with no possibility of a restricted license.

Roadside Breath Tests in Virginia

When the police officer pulls over a driver and suspects the individual may be under the influence of alcohol, the officer may ask the driver to breathe into a breath testing device. This is known as a preliminary breath test device, sometimes called a breathalyzer. This test is used to give the officer probable cause to make an arrest. These tests are not used as evidence in court that the driver's blood alcohol level was over the limit.

Can You Refuse a Preliminary Breathalyzer (PBT) Test? 

A breath test on the side of the road is not required. These breath test devices may not be reliable and could even test positive for a sober driver. It may be a good idea to refuse these preliminary breath tests.

Types of Chemical Tests After a DUI Arrest

Chemical tests after a DUI arrest are different than roadside tests. These tests can be used as evidence in the individual's criminal case. In Virginia, there are generally 2 types of chemical tests used, depending on the circumstances, including:

Breath testing is the most common chemical test used by law enforcement in Virginia after a drunk driving arrest. However, breath tests are generally limited to testing for alcohol and are not used to detect drugs or other chemical substances that may impair a driver.

Blood tests can be used to test for drugs or alcohol. When the police suspect a driver may be under the influence of drugs, the officer will generally take a blood sample. However, a blood sample can also be used to test for alcohol.

Breath Tests After a Virginia DUI Arrest

Breath tests analyze the amount of alcohol present in the driver's breath and use this measure to estimate the driver's blood alcohol content (BAC). The police have strict requirements for breath testing because these test results can be used as evidence in a criminal case. This includes:

  • Observation of the test subject,
  • Timing of the test sample,
  • Breath test instructions,
  • Breath testing machine calibration, and
  • Test equipment cleaning and maintenance.

If the police department does not follow the strict requirements for an accurate breath test measure, the suspect's DUI defense attorney can challenge the use of the results in court.

Blood Testing After a Virginia DUI Arrest

Blood tests are generally more complicated than a breath test sample. Blood tests require a blood sample taken by a trained individual. Blood samples may also have to be analyzed before the results come back with alcohol or drug levels. However, just like breath tests, blood testing requires proper training, equipment calibration, and making sure there were no problems or contamination all along the way of the blood test.

Can You Refuse a Chemical Test After a Drunk Driving Arrest in Virginia?

Subject to the requirements listed above, under Virginia's “implied consent” laws, Virginia drivers have given their implied consent to give a breath or blood sample after a DUI arrest. Most drivers never know about this consent until it comes time to give a chemical test sample after a drunk driving arrest. Refusing to give a breath or blood sample after an arrest can result in a mandatory license suspension.

Refusing a chemical test after an arrest will lead to a 1-year suspension of your Virginia driver's license. A second refusal within 10 years can mean a 3-year license suspension.

Some drivers refuse a chemical test thinking that if the police don't have evidence of the driver's BAC, the driver will not be prosecuted. However, a driver can still be charged, prosecuted, and convicted for a DUI even if he or she never gives a breath or blood test. The license suspension period for refusing a chemical test can also be as bad or worse, compared to a DUI conviction.

Challenging Chemical Tests by Charlottesville DUI Lawyer

An experienced DUI defense lawyer can challenge chemical test results, including breath or blood testing in a Virginia DUI case. Challenging DUI chemical test results requires an understanding of the law and science behind chemical testing. Talk to an experienced Virginia DUI defense attorney about your case and your best defenses. Contact me today for a free consultation.

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