Virginia DUI Breath Tests

On Behalf of | May 14, 2020 | DUI |

One of the most common ways for the government to prove a person is driving under the influence is through the use of Virginia Code 18.2-266(i). See:  This section criminalizes operating a motor vehicle while having a blood alcohol concentration (“BAC”) of 0.08 or more.  If the BAC of the driver is 0.08 or more then Virginia Code 18.2-269(A)(3) provides “it shall be presumed that the accused was under the influence of alcohol intoxicants at the time of the alleged offense.” See:

This “permissive inference” allows the judge to infer you were impaired and puts the burden on you, the defendant, to prove you were not.  As you can imagine, this is a difficult task. So often one of the most important tasks of a good DUI defense is to find a way to invalidate or exclude the Certificate of Analysis (which is the evidence used in court to establish your BAC) from ever being presented to the judge for consideration. This article will focus on one of the ways to attack and hopefully prevent the Certificate of Analysis from being considered as evidence.

The Virginia Department of Forensic Science (specifically the Breath Alcohol Section) oversees the training and licensing of breath test operators, responding to requests for records, providing testimony in courts of law, and maintaining/certifying the Intox EC/IR II breath test equipment. The Intox EC/IR II is the breath test used in Virginia for determining your BAC.

It is essential for a DUI defense attorney to have a working knowledge of the Intox EC/IR II and the regulatory and statutory requirements that govern its use. One of the most important tools for attacking the BAC result listed on the Certificate of Analysis is to know the intricacies of the Intox EC/IR II Instructional Manual. See:

Virginia Code Ann. 18.2-268.9 requires breath tests to be performed in accordance with DFS standards, including, among other steps, that a subject be observed for 20 minutes prior to blowing. Essentially, the officer needs to be present with the defendant the entire 20 minutes to ensure that person did not have anything in his/her mouth, vomit, burp, drink, etc. to prevent their from being residual mouth alcohol contamination of a breath sample. If the officer failed to follow these procedures it calls into question the accuracy and reliability of the BAC result.

Often when this type of procedural failure is challenged, the prosecution will argue that their officer need only “substantially comply” with these “procedural regulations.”  See Virginia Code 18.2-268.11   “Substantial” is not specifically defined in the code and so it can be argued that the courts must apply its ordinary and plain meaning.  Smith v. United States, 508 U.S. 223, 228-29 (1993).  “Substantial” is defined as being “of considerable importance, size or worth” and “concern[s] the essentials of something.” Oxford Dictionarie  Clearly, the common sense meaning of the term suggests that something must be done, albeit imperfectly to meet the standard of “substantial.”  So arguably, if the officer failed to monitor a defendant all during the 20 minute observation period they did not “substantially comply” under Virginia Code 18.2-268.11.