A Hennepin County judge ruled Monday that the city of Minneapolis is not allowed to manage the Commons, a 4.2-acre park outside U.S. Bank Stadium.

Activist John Hayden and former councilman Paul Ostrow sued in 2017 arguing that the city is not allowed to manage the site because, under the city charter, that's the park board's job.

The park board had said operating the Commons would be too expensive, so leased it back to the city.

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Ostrow said the arrangement skirts state limits on public subsidies for the stadium because the Vikings use the site rent-free.

"It's a really big deal when you have a judge saying that the charter has been violated," Ostrow said. "And the decision was not a close one. It was really an open and shut decision."

But city attorney Susan Segal said the agreement does not violate the charter.

"The judge got it wrong here," Segal said. "The park board and the city, we're part of the same governance structure and have worked cooperatively for years. This agreement for the Commons was one that was approved by the elected officials of both the park board and the city."

Segal said the city and park board will likely appeal the decision.