(CNN) As cities and states grapple with the future of Confederate monuments, the Alabama Supreme Court has weighed in on one: Putting plywood around its base violated state law.

The court on Wednesday upheld the state's protections of the monuments and cited Birmingham for building a black wooden box around the memorial. The city will be hit with a $25,000 fine.

Earlier this year, Jefferson County Circuit Judge Michael Graffeo overturned the Alabama Memorial Preservation Act, saying it violated the free-speech rights of communities.

That 2017 law -- directed at local governments -- bars the removal, renaming, removal and alteration of monuments, memorial streets, memorial buildings and architecturally significant buildings located on public property for 40 or more years.

Alabama Attorney General Steve Marshall had sued Birmingham for covering up the inscription on the base of the 52-foot monument from 1905 that honors Confederate veterans. Then-Mayor William Bell made the decision to have side panels at the Linn Park memorial covered while options to remove it were being considered. The top portion of the monument was left visible.

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