It's just wonderful that the criminals have more rights than the victims. 
Strange, these folks do have neighbors don't they.?
Is there any reason these old folks can't buy a cheap video camera and have it pointed outside the house to record these acts of abuse.?
There are mouse gangs here in America also. At one point I lived in a ground floor apartment in a complex that was being destroyed by these wannabe gangsters. Oldest was about 13 youngest perhaps 8 years old.
These Mice [ as I called them ] were brazen little thugs. Only about 6-7 of them but all ready becoming mean as hell.
Back then the cost of video surveillance was a new thing and very expensive, the managers of the complex told me these kids would only smash any equipment they put up.
Each time a resident identified a kid as carrying a large stick or board and actually seeing the kid break a window or tampering with someones car it came down to the old, just one word against the others.
These kids were a terror, most family's in the complex worked so their kids were home alone on school Holidays. Thing that got my goat was watching the youngest and the smallest boosted up to climb to the second floor and break a slider into an apt. and start throwing stuff off the balcony.
At that time I was on vacation so at home getting ready for a camping trip with the kids and had hauled out my old faithful Nikon Camera to be cleaned and loaded with film. I saw what was going on and without much thought started taking pictures of the break in. I got 6 kids on film, with their sticks in hand and the little kid throwing the loot to his Buddy's below.
I took the film to a one hour developing business and then straight to the managers office. I told them I had some pictures they might be interested in for sale. 2 months free rent. They looked at my pictures and we settled on just 1 months free rent and I kept the negatives. Later they gave me the extra months free rent for the negatives as the police required them.
These old folks cannot live in fear, they need to be able to fight back and as they say a picture is worth a thousand words.