There are rangers out there. It's a State Recreational Area so there are rangers on the roads and trails. CHP on the highway along with county police but they are a little sparse. If think the guys who take the cars drive off the road around guard rails or blaze a quick trail where they can't be seen. I worked with a guy who lived out of his Honda Accord for a summer at Lake Clementine. Pretty impressive considering he was in a Honda (and off road) and there is no camping down there (the "park" is closed every night). He never got caught and never saw a ranger looking for him.