How Do I Find Out My BAC From a DUI?

If you were arrested for drinking and driving, you may wonder, “How do I find out my BAC from a DUI?” The police department that arrested you may provide this information on the ticket. If not, you (or your attorney) can request this from them. Finding this information is very important because the prosecution can use it to prove their case. In turn, you can search for flaws in the test they used or how they administered it, which you can point to in defending yourself against the charges. 

At Veitch Ault Defense, we understand the frustrations people may endure if they are arrested for a DUI. Our Washington DUI attorney participated in the DWI Detection/Standardized Field Sobriety Testing (FST) training administered by the National Highway Traffic Safety Association. Along with his impressive legal background, this gives him unique insight into how these tests are used and should be administered. 

What Is the Blood Alcohol Level Limit in Washington? 

Washington law makes it illegal for someone to get behind the wheel with a blood alcohol concentration (BAC) level of 0.08 or higher. Likewise, their BAC cannot equal or exceed 0.08 within two hours after driving a vehicle. Drivers who are over 21 may not have a THC concentration level of 5.00 or higher. 

Commercial drivers (like truck operators) must follow stricter rules around alcohol and drugs in their systems. For example, Washington law prevents drivers from operating a semi or similar vehicle if their BAC is 0.04 or higher. People with a CDL may also lose this license if they get behind the wheel of a non-commercial car while their BAC is 0.08 or higher. Those who are under 21 may lose their CDL if their BAC is just 0.02 or higher. 

How Do I Find Out My BAC From a DUI?

If you were arrested for a DUI in Washington State, you may have questions about obtaining BAC test records. The ticket or police report should list the blood alcohol concentration and the type of test they used to measure this. It’s important to independently request this information and any supporting documents about the machine or method used. You can use these details to determine if the test or methods used were, in fact, reliable. 

The prosecutor may have the BAC test information and turn this over to you before trial. If not, you or your attorney can submit a discovery request to ask for this. Additionally, you may contact the police department that arrested you. They may send you a copy of the BAC report and give you details about the methods used to complete and interpret the test. 

If you have questions about your BAC results or how to request these, consider partnering with a seasoned Bellevue criminal defense lawyer. An attorney has the tools to investigate the situation and determine how to obtain and challenge the results. 

What Methods Are Used to Determine BAC in a DUI Case?

Under Washington law, the authorities can use different types of methods to measure the amount of alcohol in someone’s system. Typically, this will begin with a visual inspection of the person’s behavior. For example, a police officer may notice someone swerving in and out of their lane. The cop may use this as the basis (i.e., probable cause) to pull someone over. 

From there, the police officer may ask the person questions and, during the interaction with them, smell alcohol on their breath. They may also notice the person fumbling to find their license or unable to stand up or walk straight when they get out of the car. The police officer may perform a field test (such as having the person say the alphabet backward or walk toe-to-toe in a straight line). 

If the cop thinks the person failed any of those tests, they may use this as the basis for the person taking a sobriety test. For example, they may use a breathalyzer to measure the amount of alcohol in their system. The cop may administer this test out in the field or, in some cases, take the driver back to the station to do this. Police officers may also use a blood or urine test to detect alcohol or drugs in the person’s system. 

What’s the Relationship Between the BAC Testing Procedures and Accuracy Rates?

Each type of test has a different accuracy rating based, in part, on how it’s used. For example, some tests need to be stored at a specific temperature or calibrated correctly. Other methods of measuring someone’s BAC may require the police to wait until 15 minutes after someone vomits. When law enforcement fails to follow these procedures closely, it can lead to inaccurate results. 

Some tests are notoriously unreliable or set the accused up for failure. For example, the field sobriety tests are highly subjective and can be challenging for people to complete even if they are sober. Moreover, because the officer doesn’t test the person under normal circumstances, there’s nothing to compare the results to. In other words, the person might struggle with the test under regular circumstances. Or they could have problems completing the evaluation due to the stress of an arrest. 

How Can I Challenge the DUI Blood Alcohol Concentration Results?

One way to challenge the results of your BAC is to show that the police didn’t follow the correct procedure for administering that test. For example, you might present evidence that they failed to calibrate the device before using it. Additionally, you can use the maintenance records to show inconsistencies in the device’s results. Likewise, you might show gaps in the chain of custody, which can leave the door open for contamination. 

Depending on the situation, you or your attorney may uncover other possible ways to challenge the results of your BAC test. You can use this evidence to try to disprove the prosecution’s case against you. In other words, if you or your attorney can prove there’s an issue with the test or the results, this can be valuable evidence to use to defend yourself. 

Veitch Ault Defense: Dedicated Washington DUI Attorneys

Getting arrested for drinking and driving can be a stressful experience, potentially taking you away from your friends, family, and work. Getting a hold of the blood alcohol concentration results can help you understand the charges and how to defend yourself against them. Instead of trying to manage this on your own, consider working with a knowledgeable DUI defense attorney. 

At Veitch Ault Defense, we believe that anything worth doing is worth doing well. We dedicate our time, resources, and energy to fighting for those who face criminal charges like driving while intoxicated or under the influence. Our King County DUI Attorney has decades of experience advocating for the rights of the accused. His tireless efforts have earned him the distinction of making the selective Super Lawyers list from 2016 to 2023. 

If you were arrested for a DUI in Washington, contact us today by calling 425-970-9607 to schedule a free consultation. 


Related Posts


Field Sobriety Test vs. Breathalyzer: Differences Explained Simply

Understanding the difference between a field sobriety test vs. a breathalyzer can help you protect your rights. A field sobriety test is something that officers ...
View Article

What Happens If I Refuse a Field Sobriety Test in Washington?

When you get pulled over by the cops for drinking and driving, you may have questions regarding what happens if you refuse a field sobriety ...
View Article
Criminal Defense

Fighting a DUI Charge Based on Police Misconduct

If police misconduct leads to DUI charges or a resulting conviction, you can point to these issues to defend yourself against the allegations. Missteps or ...
View Article

We Have Successfully Defended Hundreds of DUI Cases

Reach Out to Us as Soon as Possible to Get the Best Solution For Your Case

For a free consultation to discuss your pending case or other legal matters, please call us any time at 425-452-1600 or complete our online contact form. Our attorneys will explain the entire process surrounding your charge and remove the fear and uncertainty regarding your arrest. Our team should be your first call if you need a top-rated, dedicated, and responsive DUI/DWI or criminal defense attorney. If success in your legal matters is your only option, we hope that you will place your trust in top-rated Washington State DUI attorney Robert Ault.  

Contact Us Today

Get Started with a Free Consultation

Law Firm SEO provided by Ranked.Legal