I've said this before - even a small percentage of bad people make for a lot of bad people even when the vast majority of us are good people.
I'm biased here but I'd support a 10 year prison sentence for this group of scum sucking heartless thieves. They don't even need a trial.
This is not the first time I have heard of this though and having the backyard door LOCKED with a key or combination lock can only help....