In a previous post, we examined the per se portion of the DUI law. Per se basically means “it is what it is” and there is no room for interpretation. For purposes of this section, if the defendant has a BAC above the legal limit, the defendant is guilty, even if the defendant was not “intoxicated” in the everyday sense of that word.
However, in about 20% of DUI cases, prosecutors cannot use the per se provision because the defendant refuses to take a breath test. Officers could obtain a search warrant and extract a blood sample over the defendant’s objections, but few officers take this extra step. So, court prosecutors must rely on circumstantial evidence, and this evidence is always subject to interpretation.
Circumstantial Evidence at the Scene
Officers only need probable cause to arrest someone. Courts have never defined this phrase, but it is a standard of proof somewhere between the near-absolute certainty of beyond a reasonable doubt, an idea that is discussed below, and the fact-based hunch of reasonable suspicion, which is the scant amount of evidence that officers need to pull over motorists.
To transition from the traffic stop to the field sobriety tests, officers usually rely on evidence like:
- Defendant’s Previous Stop: Officers often ask motorists “Where are you coming from?” If they say they are coming from a bar, the officer can fairly assume that they had been drinking at least moderate amounts of alcohol; if the response is “a party” or “a restaurant,” the inference is not as strong.
- Erratic Driving: Nearly all motorists get pulled over because they go through a red light, change lanes without signaling, or whatever. Such behavior could be evidence of intoxication, or it could be evidence of an overall contempt for stop signs.
- Bloodshot Eyes: Similarly, bloodshot eyes could indicate the person was intoxicated or could indicate that the person’s allergies are acting up.
- Odor of Alcohol: Officers almost always testify that they detected an odor of alcohol. If that odor came from the defendant’s breath, that is evidence that the defendant had been drinking, but if the odor came from the car or the person’s clothes, that is evidence that the defendant had been around someone who had been drinking.
Probable cause is a relatively low standard, so the judge will probably not throw out the case at this juncture, even if the evidence is shaky. However, by challenging this evidence, the defense attorney paints a picture of someone who may not have even been drinking at all, let alone intoxicated by alcohol.
Circumstantial Evidence at Trial
To convince the jury that the defendant is guilty beyond a reasonable doubt, which basically means that each juror is totally convinced even after hearing both sides, most prosecutors rely on the approved field sobriety tests.
- Walk and Turn: The defendant must “walk a straight line” heel to toe backwards and forwards.
- Horizontal Gaze Nystagmus: The defendants must follow fixed points, usually the tip of a pen or a fingertip, using only their eyes and without moving their heads.
- One Leg Stand: The defendant must hold one leg up in the air at a certain angle for a certain amount of time.
In all three, officers are trained to look for clues of intoxication. At trial, officers almost always testify that the defendant “failed” each test. Sometimes they base this assessment on technicalities, like starting with the wrong foot or a nearly imperceptible sway. Fortunately, the jury has the final say on whether the circumstantial evidence means that the defendant was intoxicated or just nervous.
Contact Experienced Attorneys
Circumstantial evidence DUI prosecutions are inherently weak. For a confidential consultation with an experienced criminal law attorney in Schaumburg, contact Glasgow & Olsson.
(image courtesy of Michael Mroczek)