The rising blood alcohol defense argues that your alcohol level was still climbing when police stopped you for DUI, so the breath or blood test taken later showed a higher number than what was actually in your system behind the wheel. Illinois law makes it illegal to drive with an alcohol concentration of 0.08 or more while driving, not at the moment you blow into a machine at the station.
That gap can be 45 minutes or longer. Breath testing typically happens well after the stop, and for some drivers that delay is the difference between a legal reading and an illegal one. If you were arrested for DUI in 2026, a Cook County, IL criminal defense lawyer can look at the timeline before anything is locked in.
How Does Alcohol Absorption Affect a Breath Test Result for DUI?
Alcohol does not enter your bloodstream the moment you swallow it. It moves through the stomach and small intestine first, and that takes time. For most people, alcohol levels keep rising for roughly 30 to 90 minutes after the last drink before peaking and then falling.