Where a defendant is charged with aggravated fleeing and eluding, the state must show that he exceeded the posted speed limit by more than 21 miles per hour and that he did so after a pursuing squad car had activated its lights and sirens.The 1st District Appellate Court affirmed in part and vacated in part a decision by Cook County Associate Judge James B. Linn.Around 3 a.m. on Dec. 25, 2013, Chicago police officer Steve Schmid and his partner were patrolling in a marked squad car. They saw a black Chevrolet Monte Carlo …