"Friends of the Parks has always said that we welcome the Obama Presidential Center to Chicago's South Side but disagree with the choice to locate it on public parkland rather than vacant land across the street from Washington Park," Juanita Irizarry, executive director of Friends of the Parks, said in a statement Monday. "While we are not involved with this lawsuit in any way, it is an indication of the fact the Friends of the Parks is not alone in our concern about Chicago's parks being seen as sites for real estate development."