If a defendant goes to trial on an OWI charge in Iowa, where no BAC was given, the jury will decide whether the driver is “under the influence.” This is commonly called a “refusal” trial, based on the defendant’s refusal to providing a sample. Remember that the PBT, or preliminary breath test results are not admissible, this “refusal” is referring to the blood, urine or Datamaster/Breathalyzer breath results.
A trial of this nature has a better chance of acquittal than a trial with a BAC result which is over the legal limit. For a result-based trial, all the State must prove the that the defendant was operating the vehicle and that he provided a test at or over 0.08. With a refusal trial, the jury must base their decision on whether the driver was “under the influence” based on the following jury instruction.
2500.5 OWI – Definition – Under The Influence. A person is “under the influence” when, by drinking liquor and/or beer, one or more of the following is true:
1. Her reason or mental ability has been affected.
2. Her judgment is impaired.
3. Her emotions are visibly excited.
4. She has, to any extent, lost control of bodily actions or motions.
As you can see, this is a rather broad and subjective definition of “under the influence.” Nonetheless, these are the criteria that a juror must use to decide the case. I will examine each of these variables in turn. And please note that the State must only prove one of the above, not all four.
Reason or mental ability has been affected: Prosecutors will argue that failure to follow the directions of the field sobriety tests is evidence of failure on this point. They can also argue that the defendant’s decision to refuse the test is evidence of affected reason.
Impaired judgment can be argued similarly to the above point. Another argument I have heard was that when a defendant was not wearing warm clothing in the dead of winter, her judgment was off. This would be more understandable if the defendant was out walking, instead of driving in her heated car.
Visibly excited emotions due to drinking beer and/or liquor is probably the most liberal definition of “under the influence” that the jury will consider. Some people get excited quite easily with or without the use of alcohol, and thus would be convicted of OWI more easily.
Finally, the prosecutor will argue that any evidence of failure on the FST’s is evidence of loss of control of bodily actions or motions. Stepping off the line on the walk-and-turn, or losing balance during the one leg stand are examples.
As you can see, these criteria are broad and difficult to objectively define. That is why they are questions left for the jurors.