A question I am frequently asked is “what is the difference between DUI, DWI, DUID, OUI, OWI?”

Each of these acronyms stands for a different type offense depending on the State in which the offense is committed, but in truth all represent a group of offenses commonly labeled driving under the influence.

The acronyms mean the following: DUI- Driving Under the Influence. DWI- Driving While Intoxicated. DUID- Driving Under the Influence of Drugs. OWI-Operating While Intoxicated/Impaired (typically used in watercraft or airplane situations). And BAC- Breath/Blood Alcohol Content over the legal limit of 0.08%. The two most common offenses are those of DUI and DWI.  The best explanation between these two is that DUI refers to behavior, and DWI refers to an actual blood alcohol content.

As part of the crackdown on drunk drivers across the country, state legislatures have passed so-called per se drunk driving statutes. These statutes do not simply treat the results of blood-alcohol tests as evidence from which a rebuttable presumption of intoxication is drawn. They actually make it illegal per se to drive with a particular blood alcohol content (BAC). The offense is having a designated amount of alcohol in the blood, which is now uniformly .08 percent. These statutes usually provide that anyone who drives with a BAC of 0.080% of alcohol in 210 liters of breath or more is guilty of a crime.

Obviously, this new type of statute greatly facilitates the prosecutor’s job– and makes it even more imperative to hire a knowledgeable attorney who is able to attack the validity of the blood-alcohol testing procedure or the machine itself. The only defenses to these per se charges are (1) the accused was not driving; (2) the test results, though accurate, do not reflect the blood-alcohol content at the time he was driving; or (3) the test results are inaccurate or the test was not administered according to legally mandated procedures.

As a general rule, per se laws coexist with the traditional drunk driving laws and the accused may be charged with violation of both offenses even though he may only be punished for one. Thus, the prosecutor is given a powerful weapon. If the suspect registers .08 percent or higher on the blood-alcohol test, he can be charged with violation of the per se statute—and easily convicted. If the suspect refuses to take the test, he can still be charged with the traditional statute that makes it criminal to drive while under the influence of alcohol; the testimony of the arresting officer and/or civilian witnesses is sufficient to uphold a conviction. Similarly, if the test results are below .08 percent, or if the jury rejects the blood-alcohol evidence, the prosecutor can still proceed under the old statute and obtain a conviction.

The most common of the offenses are DUI and DWI which if you live in a jurisdiction that classifies them separately, DUI is typically considered to be the lesser of the two charges or a situation when there is no chemical test result which is commonly referred to as a refusal. Make no mistake, a person can be charged with the offense of DUI even with no chemical test or  even if his or her blood alcohol concentration level is below the legal limit of 0.08 percent.  Some of these situations are if the driver is below the age of twenty-one (21) or has a CDL license.

As a general rule, prosecutors in most states rely much more heavily on DWI charges than on DUI charges, since breathalyzer and blood-alcohol tests results provide more concrete scientific evidence than field sobriety test results. But in many states like Illinois, police may double-charge drivers, once with DUI and once with DWI.  Further, some states will now get warrants based on the refusal to submit to a chemical test alleging that the refusal itself is an admission of guilt.

The traditional crime has been coupled with, or in some cases, complemented by, two other crimes: the crime of driving while impaired and the crime of having a particular blood, breath or urine alcohol concentration while driving or within a specified period of time after driving. The jurisdictions that have a separate charge of driving while impaired often make this a lesser included offense of driving while intoxicated. Therefore, even if the state is unable to prove the more serious driving while intoxicated or driving under the influence charge, the state may be able to show impairment to some degree, thus sustaining the driving while impaired charge.