A citizens group opposed to a business group’s development plan at Lakeside Park has officially filed a lawsuit challenging the city council’s denial of the group’s petition to put the question on the April ballot in the form of a referendum. The suit was filed this week in Fond du Lac County Circuit Court after the council voted last week to deny petitions calling for a binding referendum on future development of the lighthouse peninsula and Oven Island at Lakeside Park. The city attorney recommended the petitions be denied based on state statute that they cannot oppose actions already taken by council and are administrative and not legislative. The attorney for the group Friends of Lakeside Park, Mary Beth Peranteau says the ordinances would simply give taxpayers a say in how their tax money is going to be spent.