TO WHAT EVIDENCE AM I ENTITLED IN ORDER TO CONTEST A DUI?

If you have been charged with a DUI in Illinois, you are entitled to discovery, which is any evidence the state's attorney intends to use against you.  This can include police reports completed by the officers, videos or audio recordings of any field tests or conversations, and other written reports or documents made at the time or subsequent to the arrest.  Upon request, these documents must be turned over by the state's attorney so the defense can review them in adquate time before any trial.  A refusal to do so by the state's attorney will prevent them from using that evidence at trial and could even cause worse damages to their case.

http://www.westmontattorneys.com/Traffic-DUI/