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How Do Illinois Police Know if Someone is Driving High?

Posted on in Driver's License Reinstatement

defense lawyerRecreational marijuana has been legal in Illinois for nearly two years now. Unfortunately, some Illinois residents assume that because cannabis is legal, that there is no way to get arrested for a cannabis offense in Illinois. On the contrary, there are still many ways in which cannabis use can lead to criminal charges. Driving under the influence of marijuana is still strictly illegal. So-called “drugged driving” can lead to serious criminal penalties and the loss of your driving privileges. Many people wonder how law enforcement officers determine if a driver is under the influence of cannabis.

Driving Under the Influence of Cannabis

Illinois law states that a driver may not operate a vehicle under the influence of marijuana or other intoxicating substances. Marijuana can increase reaction time, dull senses, and decrease a driver’s ability to drive safely. However, how do police know if a driver is under the influence?

During a traffic stop, police first look for obvious signs of marijuana use. The smell of marijuana is often the most tell-tale sign. Red eyes, slowed speech, and a flushed appearance may also be signs that a driver is under the influence of cannabis. Police may also ask the driver to perform a field sobriety test that will show signs of poor balance and other possible signs of intoxication.

Police may also use THC tests to prove that a driver is intoxicated. THC is the chemical that gives marijuana its psychoactive effects. Police may ask a driver to submit to a THC test of their blood, breath, or urine. The legal limit for THC is 5 nanograms of THC per ml of blood and 10 nanograms of THC per ml of another bodily substance. If a driver’s THC level is higher than this, he or she faces an immediate driver’s license suspension and DUI charges.  

Are THC Tests Accurate?  

The accuracy of THC testing and field sobriety tests for marijuana intoxication has been consistently called into question. In a recent study, the National Institute of Justice found that THC levels in bodily fluids are not consistently accurate indicators of cannabis intoxication. Researchers did not find a strong correlation between decreased psychomotor and cognitive functioning and THC tests.  Although the reliability of THC testing is still not fully understood, the fact remains that a driver can face serious penalties for DUI involving marijuana.

Contact a Crystal Lake DUI Defense Lawyer

If you were charged with drugged driving or driving under the influence of marijuana, contact Botto Gilbert Lancaster, PC - Illinois Driver's License Reinstatement Lawyers for legal help. Our team can help you dispute the validity of the evidence against you and build a strong defense case. Call our McHenry County criminal defense attorneys at 779-800-2250 for a free, confidential consultation.





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