Police and prosecutors would have you believe that any type of blood alcohol concentration (BAC) test is accurate. If you were arrested for a DUI and the police performed any number of BAC tests, then, of course, the results of that test must be reliable. However, this is far from true. Certain tests can provide a fairly accurate BAC if you are being suspected if a DUI in Seattle. However, this is not always the case. Certain tests are inherently less accurate, and many are not properly administered on well-calibrated equipment. Despite what the police or prosecutors say, you should not assume a BAC test in your case is a hard fact.

Whether or not a BAC test should be considered reliable in court depends on many factors, including:

  • Which test was used to determine your BAC
  • When the test was administered
  • How the test was administered
  • Who administered the test
  • The condition of the equipment

After a DUI arrest, you should contact an experienced Seattle DUI attorney at Emerald City Law Group. We will thoroughly review your case, from the very beginning of the traffic stop up until now. To learn more about how we can help, call us at 206-973-0407 to schedule a free and confidential case consultation.

Breath Tests

Roadside Breath Tests
A portable breathalyzer is typically a small, handheld device an officer asks you to blow into while standing on the side of the road or sitting in your vehicle. You may have been arrested because you took a roadside breathalyzer test and blew a .08 percent or higher. This is also known as a preliminary breath test.

Roadside breathalyzers are unreliable. In many situations, the breathalyzer is not properly calibrated. These devices must be regularly and properly maintained and cleaned to ensure an accurate reading. Police departments often fall behind on this. Also, many officers do not properly administer roadside tests. They fail to observe you for long enough before a test to see if there is anything that could alter results, such as food, beverages, or vomit.

While preliminary breath tests are considered accurate enough to lead to probable cause for a DUI arrest, they may not be used against you at trial. Depending on the facts of your case, your attorney may be able to argue against the reliability of a roadside breath test when fighting your case.

Breath Tests Can Go Wrong
The most common BAC test is a breath test conducted on a more complex device at a police station. In general, breath tests (not roadside breathalyzers) are considered generally reliable enough to be used in court. However, there can be issues that lead to inaccurate BAC results.

Breath test machines use an average multiplier to determine BAC. This average multiplier does not leave room for individual physical traits. Depending on your physicality, an average multiplier may not be appropriate to determine your BAC.

Other potential errors with a breath test at a police station include faulty equipment, human error, or a disregard for proper procedure. If a test is not properly administered on well-maintained and clean equipment, then it is unlikely to provide an accurate BAC.

Blood Tests Lead to the Most Reliable BAC Results

Blood tests are generally considered the most reliable BAC test. However, they can still be flawed. Potential issues regarding a blood test include a sample being taken too late, the use of an expired test kit, and improper handling or storage of the sample. Other issues include substances and medications that could influence the test, or certain prescription medications.

A blood BAC test may be difficult to challenge, yet that does not mean you should not investigate your blood test to determine its accuracy. Your DUI attorney at Emerald City Law Group should dig into how, when, and by whom your blood test was conducted to determine if something may have led to an inaccurate result.

Urine Tests Are the Least Accurate

You can be asked to take a urine test to determine your BAC, however, this is regarded as the least accurate method of determining your BAC. Like with a breath test, a urine test requires converting information into a BAC. With urine tests, there is an average ratio use, which is not reliable for all individuals. The amount of alcohol in each person’s urine differs significantly based on many factors.

The longer it takes to have a urine test completed, the less likely it will be accurate. Since alcohol takes time to metabolize, the result of a urine BAC test an hour after a traffic stop may be much higher than a person’s BAC at the time of the stop.

Were You Arrested for a DUI in Seattle?

If you were arrested for a DUI in Seattle and went through one or more BAC tests, it is time to call a lawyer. Prosecutors are going to make it seem like they have a solid case. They will say that between the police officer’s report and your BAC results, you might as well plead guilty and get it over with. You need an experienced DUI defense attorney for that. By working with a lawyer, you have someone who will go over every inch of your case and determine the strongest defenses available to you. Their goal will be to get your charges dropped, obtain an acquittal in court, or at the very least minimize the consequences of a conviction.

To discuss how our team at Emerald City Law Group can help you after a DUI arrest, contact us at 206-973-0407 to schedule a free, initial case consultation.

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