In Chicago, it’s illegal to drive under the influence of marijuana just like it’s illegal to drive under the influence of alcohol. However, cases involving marijuana are often harder to prove than cases involving alcohol. Here’s why Chicago DUIs with marijuana are harder to prove than DUIs with alcohol:
With alcohol, scientists have spent a great deal of time and energy studying how much alcohol makes a typical person intoxicated. They’ve studied how much alcohol it takes for a typical person to lose judgment, dexterity and motor control. Using these studies, they’ve developed the legal limit that applies in most states. The legal limit is based on scientific evidence that shows where most people become impaired under the influence of alcohol.
However, marijuana effects each person differently. The scientific studies are lacking for a clear legal limit for marijuana. One person may be significantly impaired at a very low level of marijuana. Another person may have sound judgment and fine motor control with very high levels of marijuana in their system. It’s up to law enforcement to prove that you violated the law, but the jury may have trouble deciding to convict a person without any clear standard for intoxication.
Even though Illinois law prohibits driving with the active ingredient of a drug in your system, there’s a difference between the active ingredient of marijuana and marijuana byproducts. The byproducts of marijuana can stay in a person’s system for up to 30 days after the last time they use marijuana. That’s long after the active ingredients of the marijuana have worn off. The jury may not take kindly to the state trying to charge you with a marijuana DUI if there isn’t any active marijuana in your system. Even law enforcement officers and state attorneys may not understand the difference between active marijuana and the inactive ingredients that can stay in your system for weeks after your last use.
Police officers have been investigating drunk driving offenses for decades. They’ve been to training to investigate alcohol-related drunk driving, and they’re comfortable with it. However, drugged driving cases are relatively new. As the science lags behind for investigating drugged driving offenses, police training also lags behind.
Law enforcement officers may try to investigate a marijuana offense just like they investigate a drunk driving offense. If they do an alcohol investigation for a marijuana offense, the investigation is likely inadequate. When police officers don’t know how to investigate marijuana offenses, they don’t know how to properly document the facts of the case or preserve evidence.
As scientists have studied alcohol-related drunk driving, they’ve developed standardized field sobriety tests. They’ve used scientific testing to determine which tests are likely to show proof of alcohol intoxication. Unfortunately, with marijuana offenses, there are not standardized field sobriety tests.
Law enforcement officers often investigate a marijuana-related DUI case just like they investigate an alcohol-related drunk driving case. They may use the same standardized field sobriety tests that they’ve been trained to use for alcohol-related cases. These tests are not proven to show proof of marijuana intoxication or fitness to drive after using marijuana.
Some law enforcement officers receive advanced training in detecting marijuana use. This training is intensive. However, most officers who investigate marijuana offenses don’t have the training. Even when an officer has the training, they may still make mistakes or misinterpret results. The lack of standardized field sobriety testing can make a marijuana case more difficult to prove.
For alcohol cases, law enforcement can administer a breath test right at the side of the road. That can help them determine if law enforcement should make an arrest and bring the person to a police station for a more official test. The breath test is relatively simple. The person simply blows into a machine, and the machine produces a result.
With marijuana DUI cases, it’s not that simple. There’s no breath test for marijuana. Marijuana isn’t found in a person’s breath like alcohol is. If law enforcement wants to test a person’s marijuana levels, they must use an invasive and complicated blood test or an unreliable saliva test. The testing complications can make a marijuana DUI case harder to prove.
Scientists don’t know as much about marijuana DUIs as they know about alcohol DUIs. There aren’t as many formal studies to verify when a person is unfit to drive. In addition, many law enforcement officers don’t have the training to adequately detect when a person is under the influence of marijuana. Ultimately, it’s up to a jury to decide a person’s guilt or innocence. Jurors are correct to hold law enforcement to high standards when they accuse a person of a crime. For these reasons, DUIs with marijuana are often more difficult to prove than DUIs involving alcohol.
The information on this website is for general information purposes only. Nothing on this site should be taken as legal advice for any individual case or situation. This information is not intended to create, and receipt or viewing does not constitute, an attorney-client relationship. Learn more about DUI by reading this wikipedia page.