The park in front of Philadelphia City Hall should be a shining beacon of free speech — a hustling, bustling, old-school public square. After all, it is heart of local government and the epitome of citizen property.

But it isn't always treated that way.

A group of college students found that out the hard way this week. For a class assignment, Temple undergrads Maryvic Perez and Unique Ratcliff tried to interview a local worker at Dilworth Park on Monday. But Perez said an employee of the Center City District — a nonprofit that has managed the park for several years — told them they needed a permit to record video.

In footage recorded by the students, a man can be heard saying, "Ladies, ladies, ladies! I'm going to have to cut you short. You're going to have to go. I have to go get a police officer. You need a permit for doing stuff like this."

Two other Temple students, Joe Edinger and Tom Hanslin, said they, too, ran into trouble when they tried to shoot B-roll at Dilworth Park on Monday. A park employee approached them and asked if they had a permit.

After they said they didn't, another worker allegedly got involved. That man said, "I'm pretty sure you can't film here," according to Edinger. Hanslin said he also told them they could only shoot video in the part of City Hall that sits outside of the park.

Paul Levy, president and CEO of the Center City District, said college students are allowed to film in Dilworth Park: "If a [staffer] said something like that, that would have been incorrect." He also said they don't need a permit to do so.

Under the Center City District's official policy, some entities do need prior approval to film in the park, including "commercial photography and filming, documentary filmmaking, TV shows, fashion shoots, or any use that has a market audience," but not students.

This isn't the first time something like this has happened, though: In 2014, staff members for the Center City District told college students that they couldn't film without prior approval. Back then, Levy apologized and said the workers had accidentally enforced an old policy.

Given that this is a repeated problem, we asked Levy if Center City District needs to provide better training to its employees on park-goers' free speech rights. "It sounds like there's a gray area that needs to be clarified," he said. "There's no doubt about that."

But perhaps a lack of training isn't the problem. Maybe it has deeper roots than that. In an email, Levy told George Miller, the students' professor, that "we like to have advance notice and have folks sign a release." Another Center City District employee told Miller via email that the students need to fill out a release form and waiver of liability, after which she said the organization "will issue the class a permit."