Chicago DUI charges get dismissed most often when pretrial motion practice knocks out the state's key evidence. The frequent dismissal triggers are: the traffic stop was unlawful (no reasonable articulable suspicion), the arrest lacked probable cause, the breathalyzer was not properly calibrated or the officer was not certified under 20 IL Admin Code 1286, the 20-minute observation period was violated, the field sobriety tests were administered outside NHTSA standards, or discovery violations where the state cannot produce required evidence like squad video within statutory windows. Non-motion dismissals happen when a critical civilian witness will not appear, when the officer fails to appear at trial, or when a lab technician cannot testify to breath test foundation. Not every case has a dismissal path.
