A common misperception concerning DUI law is that you can only be convicted of the offense if you have a breath or blood alcohol content (BAC) of .08 or higher. While RCW 46.61.502 (1)(a) prohibits driving a vehicle with a BAC of .08 or more within two hours of driving, subsection b of the same statute prohibits driving under the influence of alcohol if it affects your driving without regard to whether you are over the .08 limit. Therefore, those who end up being charged for driving with a BAC of .08 or higher can take it for granted that they will also be charged with the second offense of driving under the influence of alcohol. However, even if one has a BAC of less than .08, under subsection (1)(b) of RCW 46.61.502, one may still be charged with DUI because the arresting officer believes that his or her driving was affected by alcohol.

While subsection (1)(a) of the DUI law provides a set .08 legal limit for the BAC, how much alcohol does one need to consume to be under its influence under subsection (1)(b)? Let us approach this question by first disclosing that RCW 46.61.502(4) states that any evidence that the driver has a BAC of over 0.00 may be used to prove that the driver was under the influence of or affected by alcohol. In other words, a person can technically have a one alcoholic drink, whatever it may be, and be arrested for DUI with the results of the BAC test, whatever that may be, provided as evidence of DUI. How much alcohol consumption is necessary to be arrested for DUI is not just a matter of an individual’s level of tolerance for liquor, but how an officer interprets that individual’s behavior and actions.

Because one may be arrested for DUI on the basis of a very subjective and highly discretionary standard, I believe the law is quite confusing and deceptive. The Supreme Court of Washington, however, disagrees. In State v. Franco, 96 Wash.2d 816, 825, 639 P.2d 1320 (1982), the Court stated as follows:

…although one can legally drink and drive (citations omitted) our DUI law makes it perfectly clear that the two activities cannot be mixed to the extent that the drinking affects the driving, or the driver has a 0.10 percent of alcohol in his blood. No further specificity is required if the statute gives fair warning of prohibited conduct (citations omitted).

The decision was handed down by the Supreme Court of Washington in 1982 when the legal limit for the BAC test was still .10. While one may not realistically know what his or her BAC level is during consumption of alcohol, the law does set an empirical standard of .08 for establishing guilt. However, under subsection (1)(b) of RCW 46.61.502, determining that someone is driving under the influence of alcohol is not a quantitative, but an extremely qualitative judgment. I am not referring to individuals who are falling down drunk, but to those who consume a little alcohol to just get that slight buzz or feel relaxed. The reality is that if one consumes alcohol then one is biologically, and potentially legally, under the influence of alcohol.

Considering that DUI is a criminal offense which impacts so many lives, eliminating any confusion in this area of law should be a legislative and judicial priority. A bright-line rule which prohibits drinking and driving would provide the public with clear notice of prohibited conduct. Rather than placing someone in a position of guessing how much alcohol he or she is allowed to consume prior to driving or having an officer determine that one is driving under the influence of alcohol on a potentially touchy-feely basis, any confusion concerning the law would be eliminated if drinking and driving were absolutely prohibited. As much as such clarity would be beneficial to all parties and actors involved in a DUI setting, establishing such a clear standard would face major political obstacles.