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What is the Intoximeter? How does it work? We have the answers.

When a police officer suspects a driver in Maryland of driving under the influence (DUI) of alcohol or illegal drugs, he or she may administer one or more tests to the driver to determine whether the driver is impaired. One such method is the administration of a breathalyzer test. There are two types of breathalyzer tests in Maryland. The first is the preliminary breath test, which is administered at the side of the road. The second type of breath test is administered at the police station. The device used to administer this type of test is called the Intoximeter. Although such tests are generally trustworthy, errors in their administration or calibration can lead to inaccurate results. Specifically, such errors can result in an incorrect blood alcohol content (BAC) level reading, which can ultimately result in an innocent driver receiving a DUI charge. In this article, we discuss the Intoximeter and breath samples in Maryland DUI cases.

The Intoximeter

In Maryland, breath tests are administered using the Intoximeter EC/IR II. EC stands for electro-chemical, and IR means infrared. These represent two different ways to measure ethanol in the blood. The infrared method accomplishes this by relying on the absorption of infrared light by alcohol in the sample chamber. The electro-chemical method, also called the fuel cell method, converts ethanol and oxygen into acetic acid and water. The process creates an electrical current proportional to the concentration of alcohol in the blood, which can then be measured. The police officer who administers a breath test using the Intoximeter is required to be trained and certified in the operation of the device. In addition, the machines themselves must be regularly certified and tested to ensure they are functioning properly.

Intoximeter Results

BAC test results have legal significance. If a driver’s BAC result is .08 or more, then he or she is considered per se under the influence. If a driver’s BAC result is above .07 but under .08, then this is considered prima facie evidence that the driver is impaired by alcohol. If the test result is over .05 but under .07, then the test evidence is considered neutral. And if the test result is .05 or less, then the driver is presumed to not be under the influence of alcohol. In addition, for a driver who is less than 21 years old, the legal BAC limit is .02.

Reliability of Breath Tests

As noted above, there are two variations of breathalyzers:

• There is the preliminary breath test, which is administered roadside by a police officer to a driver suspected of DUI. This type of test cannot be used against a person in court. Rather, it is a tool to help determine whether an officer has probable cause to arrest a DUI suspect. You may refuse a prelimiary breath test without any penalty in Court.

• The breathalyzer at the police station is the Intoximeter. It is the machine that you were likely tested on if you submitted to a breath sample in a DUI case in Maryland. Intoximeter test results are admissible as evidence of a person’s guilt in court, subject to challenges we discuss below.
  Although the Intoximeter is generally considered to be accurate, there are ways to challenge Intoximeter test results in court.

Challenging Breath Test Results

Depending on the facts of the case, a skilled DUI defense attorney may be able to successfully challenge the results of a breath test result, thereby excluding it from evidence at trial. There are several ways that an experienced attorney can successfully challenge such results. For example, if the Intoximeter was not properly calibrated prior to a DUI suspect’s breath test, then an attorney can challenge the results in court. In addition, if the technician who administered the test was not sufficiently qualified to operate the machine, then a criminal defense attorney can use this fact to challenge the admissibility of the DUI test results. Further, there are timing requirements regarding the administration of the test, and if these are not followed, then a qualified attorney can have the results excluded from evidence.

Contact a Maryland DUI Attorney

If you have been arrested or charged with DUI in Maryland, you need an experienced criminal defense attorney in your corner. At FrizWoods, we pride ourselves on being one of Maryland’s most accessible law firms. Our 24-hour attorney line is always open, giving our clients direct access to our experienced criminal defense attorneys at all times. Attorneys Max Frizalone and Luke Woods know what it takes to successfully challenge DUI charges, and we will use our experience and knowledge to fight for your freedom. Please contact us today to schedule a free initial consultation with one of our talented DUI defense attorneys.