Scientific & Legal Defenses to a DUI Charge

The legal limit in Michigan is .08, but there are several scientific and legal defenses to a drunk driving charge. Government ad campaigns and slogans such as, "Over the Limit, Under Arrest," coupled with a misguided faith in the legal system result in many wrongful convictions. Unwittingly, innocent people accept plea agreements every day based upon faulty chemical tests. In other instances, guilty people plead guilty when legal defenses could have been successfully raised. The vast majority of DUI cases go unchallenged.

Machines, as well as police officers, make mistakes. A person accused of operating while intoxicated should never be overwhelmed by misgivings and doubt just because the government's machine claims that the driver was above the legal limit. Likewise, a guilty person should never assume that the police officer's case is rock solid. Police officers who make mistakes typically acknowledge those mistakes, and simple human error can result in a dismissal.

Scientific Defenses: Winning a Not Guilty Verdict for an Innocent Client

Nearly every drunk driving prosecution includes common elements that include a description of the vehicle in motion, signs of consumption, field sobriety testing, and a chemical test. By providing information in a systematic, progressive manner, prosecutors present a theory that, "if it looks like a duck, swims like a duck, and quacks like a duck, then it probably is a duck." This appeals to jurors even though studies have repeatedly shown that trained police officers frequently cannot tell whether a person is intoxicated.

Generally, the prosecutor will present a case that reveals some type of abnormal driving or an accident that brings a police officer into contact with the driver. The driving infraction is used to justify the initial stop but may also serve as circumstantial evidence of intoxication. Upon personal contact, the officer is trained to describe a variety of signs of consumption, e.g. odor of intoxicants, slurred speech, blood shot eyes, etc. The signs of consumption are used to justify the driver's further detention for field sobriety testing.

In some cases, the officer's description of the vehicle in motion may not provide circumstantial evidence of impaired driving. For example, a traffic stop may be effectuated because of an equipment violation, expired license tags, or a driving infraction that is not affiliated with impairment, e.g. speeding, driving while texting, failing to use the far right lane on a multi-lane road, etc. While these violations justify a traffic stop, they do not support a finding that the motorist is driving with less than ordinary care due to the consumption of alcohol or a controlled substance. Even driving behaviors affiliated with intoxication have alternative explanations. Weaving or touching lane markers, for example, is a common driving infraction that is frequently caused by distracted driving.

Likewise, a police officer may detect signs of consumption but these factors might prove to be meaningless. For example, the odor of intoxicants might be described as "a very strong odor of intoxicants," even though the officer will acknowledge that the odor of an alcoholic beverage cannot be used to determine whether a person is intoxicated. (A strong odor is produced by lower alcohol content drinks such as beer, while high proof vodkas produce practically no odor.) Other factors might also mitigate against any consumption of alcoholic beverages. A person's normal manner of speaking might be described as "slurred speech," and glassy eyes are produced by allergies, contacts and exposure to cold air. Finally, some medical conditions may actually make a person appear to be intoxicated. Diabetics in insulin shock, a driver who suffers a stroke, and a recent head injury can all mimic signs of consumption. Even sleep deprivation can result in signs of consumption.

Continue to Scientific Defenses: Field Sobriety Testing