Jose Lopez, a 38-year-old fisherman from Bell, stepped gingerly to the bluff's edge. He scanned the trail where, for years, beachgoers who don't live in Palos Verdes Estates have complained that they get bombarded with rocks thrown by a local surf tribe that calls themselves the Bay Boys. He noted that from the beach, 100 feet below, he would not be able to see the parking area, where outsiders' cars have been vandalized. A burly man, Lopez knitted his forehead and decided to drive away rather than head to the beach and start casting for perch. "Everyone knows how it...