The Illinois Courts Commission is poised to decide whether to suspend or retire a Cook County judge who allowed a law clerk to sit in her stead and has since been diagnosed with Alzheimer’s disease.After listening to attorneys for the Judicial Inquiry Board and Circuit Judge Valarie E. Turner argue over the merits of her case for 75 minutes, the commission announced on Tuesday it was taking it “under advisement.”Under state law, there is no set timetable for the commission to return its decision; it only …