In Washington DUI law, 0.15% is where everything changes. Below that number, you face standard DUI penalties. At or above it, mandatory minimums double. Jail time increases. Fines jump. The prosecution treats your case as aggravated. One reading. One threshold. Consequences that diverge dramatically based on which side of the line you fall.
Here’s what makes this especially frustrating: breath test machines have inherent error margins. A person whose true BAC is 0.13% might blow 0.15% due to normal instrument variation. Someone at 0.14% could register 0.16%. The line between standard and enhanced penalties is precise. The technology measuring it is not.
Eastside DUI has defended clients facing .15 BAC threshold cases in King County for 15 years. Our attorneys—Roberto Yranela, Matthew Skau, and Robin Tu—understand that when enhanced penalties hinge on a specific number, attacking that number becomes the entire case. A Bellevue, WA DUI lawyer from our team can examine your test results and determine whether you truly crossed the threshold—or whether machine error put you there.
Contact us for a free consultation.
Why Choose Eastside DUI For .15 BAC DUI Defense In Bellevue, WA?
The Threshold Is Our Target
Most DUI defenses aim for complete dismissal or acquittal. Those remain goals in .15 BAC cases too. But there’s another victory available here that doesn’t exist in standard DUI cases: getting below the line. If we create reasonable doubt about whether your true BAC reached 0.15%, the enhanced penalties evaporate—even if the underlying DUI charge stands. That partial win translates to real consequences: half the mandatory jail time, lower fines, shorter ignition interlock periods.
A Bellevue .15 BAC DUI attorney focused on this threshold understands that breath test challenges aren’t abstract arguments. They’re the path to cutting your exposure in half.
Roberto Yranela has defended clients against enhanced BAC allegations since 2013. He approaches these cases by dissecting everything that could have pushed your reading above the line when your actual BAC was below it. Partition ratio variation. Mouth alcohol contamination. Calibration drift. Rising blood alcohol. Each factor represents a potential explanation for why the machine showed 0.15% when reality was 0.13% or 0.14%. His degrees from the University of Washington and Valparaiso University School of Law provided the foundation for this technical approach to DUI defense.
Proven Track Record in DUI Cases
Super Lawyers named Roberto Yranela among the Top 40 Under 40 for DUI defense. The National Trial Lawyers recognized him in their Top 40 Under 40 as well. Avvo awarded him Client’s Choice distinction. When you need a DUI attorney in Bellevue who understands how to fight the .15 threshold specifically, our credentials reflect years of doing exactly that.
Precision Problems Work in Your Favor
The state chose 0.15% as its enhanced penalty threshold. That choice demands precision the state’s testing equipment cannot reliably deliver. We exploit that gap between the law’s demands and technology’s limitations.
What Our Clients Say
⭐⭐⭐⭐⭐ “It was easy working with Roberto! Our appointment was quick, he kept me informed of what he needed from me and followed up immediately as well. He took care of everything smoothly and was able to dismiss my traffic ticket. I highly recommend Roberto and I will be using him again if ever needed!” – Ashley Wadsworth
Types Of .15 BAC DUI Cases We Handle In Bellevue
The consequences of crossing the .15 threshold vary based on offense history and case circumstances. Our DUI defense attorneys handle every variation.
- First offense at .15 BAC. Without prior DUI history, testing at exactly 0.15% doubles your mandatory minimum jail from one day to two. A Bellevue DUI lawyer who can create doubt about that extra 0.07% above the legal limit saves you a day in custody—and all the associated consequences of enhanced classification.
- Borderline readings (.15-.17). When your result hovers just above the threshold, the margin of error argument carries maximum weight. Accepted breath test tolerances of ±0.01% or more mean a 0.16% reading could reflect a true BAC of 0.15% or below. Challenging breathalyzer results in borderline cases offers realistic paths to defeating the enhancement.
- Second offense at .15 BAC. The stakes multiply. Standard second offense carries 30 days mandatory minimum. At .15 BAC, that jumps to 45 days. Fifteen additional days in jail—potentially the difference between keeping your job and losing it.
- Third offense at .15 BAC. Third offense penalties already mean 90 days minimum. The .15 threshold pushes that to 120 days—a full extra month of incarceration riding on whether the machine’s reading was accurate.
- Readings significantly above threshold. Even at 0.18% or 0.20%, challenges remain viable. The further above 0.15%, the less likely we eliminate the enhancement entirely—but undermining confidence in the overall reading can still benefit plea negotiations and sentencing arguments.
- Medical factors affecting results. Diabetes, ketoacidosis, GERD, and certain diets produce compounds that breath machines misinterpret as alcohol. Knowing your rights after arrest includes understanding how your medical history might explain an artificially elevated reading.
Washington Legal Requirements For .15 BAC DUI
Washington law establishes 0.15% BAC as the threshold separating standard DUI from enhanced DUI. The consequences of crossing that line are codified precisely.
Under RCW 46.61.5055, BAC at or above 0.15% triggers enhanced mandatory minimums:
First offense: Minimum increases from 1 day to 2 days jail. Fine minimum rises from $990.50 to $1,195.50. Maximum remains 364 days and $5,000.
Second offense within seven years: Minimum jumps from 30 days to 45 days jail. Fine minimum increases from $1,195.50 to $1,545.50.
Third offense within seven years: Minimum rises from 90 days to 120 days jail. Fine minimum increases from $2,045.50 to $2,545.50.
The Washington State Patrol establishes breath testing protocols, including calibration requirements and operator certification standards. These protocols exist precisely because breath testing requires careful controls to produce reliable results. When those controls lapse, results become questionable—especially results that happen to land exactly at penalty thresholds.
The Washington Department of Licensing considers BAC level when determining ignition interlock duration and other administrative penalties. Higher readings mean longer restrictions. A DUI lawyer in Bellevue challenges the BAC reading across both criminal and administrative proceedings, pursuing consistent strategy in both forums.
Critically, the prosecution bears the burden of proving BAC reached the .15 threshold. Reasonable doubt about whether you actually hit that number defeats the enhancement—even if the jury convicts on standard DUI. A Bellevue DUI attorney frames arguments specifically around threshold doubt when readings fall near the line.
Challenging .15 BAC Readings In Bellevue
A Bellevue .15 BAC DUI lawyer employs specific strategies targeting the enhanced threshold:
- Margin of error arguments. Scientific literature establishes that breath testing instruments have inherent uncertainty ranges. Industry standards acknowledge ±0.005% to ±0.02% or more depending on conditions. We present this uncertainty to demonstrate that a 0.15% or 0.16% reading cannot reliably prove actual BAC reached the threshold. Our drunk driving defense team translates technical literature into arguments juries understand.
- Partition ratio variability. The 2100:1 breath-to-blood ratio that machines assume doesn’t apply to everyone. Your personal ratio might be 1700:1 or 1500:1. If so, the machine overstated your true BAC. A reading of 0.16% on the machine could represent 0.12% in your blood. This isn’t speculation—it’s documented biological variation.
- Temperature effects. Breath test machines assume body temperature of 98.6°F. Fever, recent physical exertion, or even normal variation can elevate breath temperature—and every degree above normal artificially inflates the reading by approximately 7%. Someone with a slight fever and a true BAC of 0.14% could easily test at 0.15% or higher.
- Mouth alcohol contamination. The 15-minute observation period exists because residual mouth alcohol dramatically inflates results. GERD sufferers, people who recently burped or experienced acid reflux, those with dental work trapping alcohol—all may produce readings far above their true blood alcohol level. Knowing what to avoid saying during your stop matters, but what happened during the observation period matters for different reasons.
- Calibration timing issues. We obtain maintenance records showing when the specific instrument was last calibrated. Machines drift between calibrations. An instrument tested at the edge of its calibration window may have drifted enough to push borderline readings over thresholds they shouldn’t cross.
- Rising BAC at the threshold. If your BAC was climbing when tested, the station reading may have been 0.15% even though your driving BAC was 0.12% or 0.13%. Professional testimony about absorption rates can place your true driving BAC below the threshold even when the test showed you at or above it. Working with a DUI defense attorney who coordinates specialist witnesses strengthens this defense significantly.
Contact Eastside DUI
The .15% threshold represents one of the most consequential lines in Washington DUI law. Cross it, and penalties double. Stay below it, and standard consequences apply. When your reading lands at or near that threshold, the accuracy of the number that put you there deserves serious challenge. Our Bellevue .15 BAC DUI lawyers have spent 15 years questioning these readings and fighting enhanced penalties for clients whose true BAC may never have reached the line.
We offer free consultations to analyze your specific test results and circumstances. DUI defense fees start at $3,500, and we’re direct about costs from the outset.
One threshold. One number. One chance to challenge it. Contact Eastside DUI today.
