The city of Grand Haven stopped the cross display in 2015 after critics said it was an illegal endorsement of religion. Michigan courts have said the city has the power to manage the property along the Grand River.
The Supreme Court on Monday declined an appeal by cross supporters, who said their free speech rights are being violated by Grand Haven.
The Dewey Hill monument was donated to Grand Haven as a memorial for soldiers who served in the Vietnam War. The pole was turned into a cross during summer concerts sponsored by First Reformed Church.