The “Occupy Wall Street” demonstrations against capitalism have morphed into police controversies with the arrest of about 700 people on the Brooklyn Bridge last Saturday and the Union Square pepper-spray incident the weekend before. But the ongoing occupation of Zuccotti Park—dubbed “ Liberty Square” by the protesters—in the financial district remains the center of the burgeoning protest and raises interesting constitutional issues about New York City’s ability to control activity in the park, including protesters sleeping there.

Though Zuccotti Park appears to the eye to be a conventional public park, it is not, and that raises a number of complicated legal issues, some of which the U.S. Court of Appeals for the Second Circuit addressed in 2002 in a dispute over First Amendment activity at Lincoln Center in Manhattan. As for protesters’ right to sleep in the park, press accounts suggesting they have won that right in New York City are not entirely accurate. With the occupation of Zuccotti Park entering its third week and no end in sight, these legal issues may come to the forefront.

Sleeping Protesters