I realise there's no law but I've been on some forums where the spotted threads are pretty specific. "On xyz street just past the park" and even ones where they've taken the photo of the car in the garage while the door was open for a fleeting moment. I'm probably overly paranoid, being involved with dirtbikes and personally knowing several cases here in Canberra where guys were followed home from their ride (bikes on the ute) and bikes stolen from the garage that night.