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Is presecription medication a defense to an Illinois DUI?

When most people hear that someone is charged with a DUI, they immediately think that person got arrested for driving while under the influence of alcohol. While the majority of DUIs do involve alcohol, a person can also get a DUI for driving under the influence of other substances as well.

According to Illinois DUI laws, it is illegal to drive with any amount of illegal drugs in a person’s system, including marijuana. This means that, unlike driving under the influence of alcohol in which it is technically legal to drive with a BAC of 0.08 or less, there is no tolerance level of illegal drugs under which a person is allowed to operate a motor vehicle. While this law may seem unfair, it is due, in large part, to the public policy against consuming certain controlled substances, as well as the lack of reliable scientific data about how those drugs affect a person’s ability to drive safely.

But, what if somebody has a prescription for the substances in their system? Can someone still get a DUI for driving under the influence of prescription medication? The short answer is yes.

The Illinois DUI law states that it is illegal to drive under the influence of a drug, combination of drugs, or combination of alcohol and drugs, if it renders a person incapable of safely operating a motor vehicle. This means that if a person takes medication that makes them dizzy, drowsy, or impairs eyesight to a degree that it negatively affects their ability to drive, that person can then be charged with a DUI. Further, the DUI law specifically states that it is not a defense that the person was legally allowed to have/consume such substances if it impairs their driving. Whether or not a Court would find a person taking legally prescribed medication guilty of DUI will come down to the specific facts arising at the time of the incident, including evidence of how that person was driving and his/her performance on the field sobriety tests. As can be imagined, if a person consumed alcohol on prescription medication, this can also have a negative impact on the case.

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If you, a family member or friend has been charged with any criminal or traffic matter, we urge you to contact an experienced attorney. Such an attorney will carefully evaluate your case and explain the legal options available to you at no charge.

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