I have lived in Sutton for 8 years and have always found it to be really safe and friendly. Someone else commented on Hells Angels whom I have NEVER seen; they are NOT a problem Generally Sutton is like a welcome breath of fresh air:there is almost no crime, people still leave the doors unlocked, and keep an eye out for each other and visitors. Drivers may go a little too fast up Maple Street leading to the mountain but that is about it!
Even though Sutton is probably the last place you'd expect to have crime, it happens. In the village you'll likely see a few Hell's Angels on their motorcycles, and they're notorious for organized crime. Murder is not common at all, but it has happened at least once that I know of, and it was the reason for my last trip there (for the funeral - I'd rather not speak of it).