 State constitutions provide free speech protections similar to those of the U.S. Constitution. In a few states, such as California, a state constitution has been interpreted as providing more comprehensive protections than the First Amendment. The Supreme Court has permitted states to extend such enhanced protections, most notably in Pruneyard Shopping Center v. Robins. In that case, the Court unanimously ruled that while the First Amendment may allow private property owners to prohibit trespass by political speakers and petition-gatherers, California was permitted to restrict property owners whose property is equivalent to a traditional public forum (often shopping malls and grocery stores) from enforcing their private property rights to exclude such individuals. However, the Court did maintain that shopping centers could impose "reasonable restrictions on expressive activity". Subsequently, New Jersey, Colorado, Massachusetts and Puerto Rico courts have adopted the doctrine; California's courts have repeatedly reaffirmed it.
