Driving Under the Influence (DUI, DWI, drunk driving) in Illinois is illegal under several different scenarios. You can be charged with organic DUI, or in other words, DUI based upon proof of alcohol impairment. This is shown by the police officer’s observation of your actions and conduct from the moment you are stopped to the time he releases you at the jail.
These garden variety observations for signs of a possible Illinois DUI arrest include how to conduct yourself leading up to the stop. Covered here would be how quickly you pulled over, your maneuvers while pulling over and your parking.
The officer would also observe your performance before exiting the vehicle. Here the police would be looking for any difficulties in retrieving your drivers’ license, insurance card and registration. It would extend to your ability to follow his instructions, to engage in a cogent conversation and to understand your location and surroundings. Finally, your speech, the condition of your eyes and your general physical appearance would come into play.
The next step in the observations is the so-called exit sequence. That would cover things such as any assistance you required in stepping out of the vehicle and in walking to the squad car. Moreover the officer would take your balance and coordination into account.
Illinois DUI Lawyer Blawg

