It’s a big week for Illinois politics. By the end of it, we should know whether the Illinois legislature will legalize marijuana, expand gambling, and approve billions of dollars in construction projects. As if that weren’t enough, Illinois’ entire system for taxing income could be upended. Voters will decide whether to keep the current flat tax, or move to a graduated income tax. WBEZ’s Melba Lara talks with Illinois politics reporter Tony Arnold for the latest.