CHICAGO (AP) – A federal judge will rule on the city of Chicago’s request to toss a lawsuit aimed at halting President Barack Obama’s museum and library from being built in a public park.

U.S. District Judge John Robert Blakey heard oral arguments last week in the case and said he would issue a ruling Tuesday. Protect Our Parks wants to stop the $500 million Obama Presidential Center from being built in the selected location. A ruling in favor of the group could signal that the Obama Presidential Center is in real trouble.

The parks advocacy group accuses the city of illegally transferring park land to a private entity, The Obama Foundation. City lawyers say Protect Our Parks misread the law, has misrepresented how the approval process worked and exaggerated potential environmental disruptions.