As someone who did the cache yesterday (and spotted the "Guard Dogs" sign not a million miles away) I would like to add my 2 pence worth.
We're currently on our second dog. Our first was a rescue Boxer. Charming dog, absolutely lovely with kids and babies alike. Obviously we were careful that the kids weren't left with her alone (I've always believed that ANY dog can turn).
The problem was that she just did not like little dogs. She would attack any dog that was smaller than her (this is quite common with boxers I believe). For this reason, we had to really keep an eye on her.
The one time she managed to get away (slipped her lead) she attacked a small dog (s***zu or something). She didn't do any damage (she was old and hardly had any teeth left) HOWEVER, the woman owner reported us to the Police. They came round, read us the riot act and then went away to decide whether or not they would charge us. We then received a letter telling us that she was going to prosecute anyway (as well as other solicitors letters).
Let me point out at this stage that there was NO physical damage to the dog. This lady was suing us for her dog's STRESS! This may seem a bit odd, but it was a matter of hundreds of pounds at this stage (fortunately for us we had insurance)
Anyway, upshot of this is unfortunately our dog died (one of the reasons we later found out that she was aggressive to other dogs was because she had Cancer which wasn't showing up) so the case was dropped. If it had gone ahead as a minimum my wife would have received a caution.
Now I'm not sure if anyone understands that being a registered childminder means basically no criminal record, but even worse we would have a registered dog in the house which has a black mark against it (a real no-no).
She never went out without a Muzzle ever again (I bought one of ebay for about 6 pounds - less than a months insurance)
I know this has gone OT a bit (sorry) BUT what it does point out is that if a dog is dangerous (or aggressive) then the Police WILL get involved and DO take it seriously.
REPORT THEM! IF THIS DOG ATTACKS A CHILD, IT COULD BE FAR WORSE!
Muzzles are cheap, effective and don't hurt the animal. If the fella had this dog on a lead in this area then he obviously knew it was aggressive.
Unfortunately it's owners like this that give dogs a bad name.