While you may not know this, Illinois DWI law applies to several kinds of impaired driving, including drunk driving and driving under the influence of drugs (legal or illegal.)
Odd as this may seem, a great number of people seem to think that just because they have a prescription for a drug that it is OK to drive while under its influence. Such is not the case in Illinois, and you will find this out the hard way if you are pulled over and stop checked, and the officer feels you are driving impaired. In plain English, any drug that impairs your ability to drive is banned under the Illinois DWI law.
Illinois also has a statutory blood alcohol (BAC) limit as well as an impaired driving provision. When referring to the stat blood alcohol limit, it is .08 which means if you happen to be stopped for any reason and take a test that says your BAC is at or over .08, you are automatically legally guilty of DWI. This applies even if your driving didn't seem off kilter.
Having said that however, there is an exception to the rule and that is, even if you have a lower level than .08, if you have ingested anything to drink or have taken any type of drugs and your driving is less than stellar, you may be charged with DWI. Of course if the BAC is higher than .08 consider your license gone for 90 days. Once your license is suspended you have a 45-day grace period to fight charges and still continue to drive. On day 46, unless you have contacted a highly skilled DWI attorney, your suspension is a done deal.
Many DWI attorneys tell their clients to refuse to take the BAC test and call them right away. While this is good advice, if something does happen that messes up the usual process of your lawyer being able to mitigate charges, or get them dropped, you may lose your license for 6 months. If you are subsequently convicted on a first time offense, the law mandates a one-year suspension, so you can see why you would want to speak to an expert DWI attorney as quickly as you can.
The best advice any competent Illinois DWI lawyer can give you if you drink and drive in Illinois and are stopped, is to call an attorney immediately and do not speak to anyone until your attorney arrives.