The Harold Washington Library, appropriately enough, marks the 30th anniversary of its namesake's election as mayor with a program at 6 p.m. April 15. Former maverick aldermen Helen Shiller and Dick Simpson, now a University of Illinois at Chicago political-science professor, discuss Washington's legacy along with Professor Timuel Black Jr. Laura Washington is the moderator. The event is free and open to the public at 400 S. State St.