Unfortunately "Area Banishments" have been the law in other areas, and upheld by their state courts: see North Carolina's "STANDLEY v. TOWN OF WOODFIN -and Indiana's "DOE v. TOWN OF PLAINFIELD, INDIANA"4-9-2011 California:
The Orange County Board of Supervisors, on April 5 voted unanimously to adopt a new law banning registered sex offenders from county parks, harbors, beaches and playgrounds.
According to an Orange County District Attorney’s Office press release, the ordinance, developed and proposed by District Attorney Tony Rackauckas and Fourth District Supervisor Shawn Nelson, makes it a misdemeanor for registered sex offenders to enter county recreational areas where children regularly gather without permission from the OC Sheriff's Department.
"Orange County has taken a huge step in creating a safety zone for our children," said Rackauckas. "Parks, harbors and beaches belong to families and children, not registered sex offenders."
The ordinance is set to take effect Thursday, May 5. Enforcement in parks and harbors will be entrusted to the OCSD. Violators could face up to six months in jail and/or a $500 fine. ..Source.. by Andrea Swayne (Ordinance found at link)