For the OP (MOnica) did you deliberately or accidentally miss the word "allegedly" from your headline? And the pages of comments discussing what a terrible act of vandalism it was, well, indeed so, but have they actually been found guilty?
If so, I must have missed it, but as they're appearing at a higher court next month, I don't think I did.
Don't get me wrong, IF the police have actually apprehended the right people, then I'd have them doing Community Service for just about ever, and their entire range of State Benefits would be forfeited (in MY country, that would be society's response to any anti-social crimes).
But the Police aren't always right, by any means, are they?