When you drive in Illinois, you might benefit from understanding why police officers decide to stop certain cars and what makes them look for further signs of impairment.
Excluding stops at properly organized sobriety checkpoints, law enforcement officers must have probable cause for DUI stops and arrests. When an officer cannot point to specific, legitimate reasons he or she believed a driver was impaired, the prosecution's case can suffer.
Types of driving that trigger suspicion
Generally, police officers begin to suspect impairment based on certain driving behaviors. These commonly include weaving or drifting, abrupt stops and starts, failure to obey traffic lights or signage, speeding and other reckless conduct. Officers arriving at the scene of a car crash may also suspect impairment.
During the stop
Once they stop the car, officers will observe the driver's appearance and demeanor for signs of intoxication. A smell of alcohol or drugs on clothing or inside the vehicle, slurred speech, a disheveled appearance and a lack of physical coordination may all indicate impairment. Other common symptoms include bloodshot eyes and shakiness.
The field sobriety test
If the officer observes any of these or other signs, he or she may ask you to get out of the car to watch your ability to move while keeping your balance. Officers may ask you to take a field sobriety test. You do not have a legal obligation to do this, and you generally should not. Passing may not save you from arrest, and bad results can add to the weight of the evidence against you. For a number of reasons, you can fail a sobriety test even if you have not taken any alcohol or drugs at all, especially if you suffer from certain health conditions or take some kinds of medication.
Implied consent and chemical testing
If you are arrested or stopped for DUI, the law requires you to provide a blood, breath or urine sample for chemical testing. Potential consequences include license suspension for at least a year, even if you ultimately obtain an acquittal in the underlying DUI case.