Oh sure because comfronting a criminal in his own home is one of your best ideas yet.
What if he is mentally unstable? What if he attacks you or pulls a weapon?
Phone the damn police and stop being an idiot.
im thinking of the new born not the crime.
Crikey, you really are a forgiving and generous neighbour!Ok i will pop around on sunday and have a word. I will spell it out if he wants my wife and ....

Could you blackmail him?
I love how black and white these situations are to everyone. If you found out your Mum had nicked a tank of petrol, would you call the police? Assuming the majority of you are normal and would not try to have your own mother sent down - there is a line between your dear old mum and a "good guy" neighbour of 2 years - Everyone has to draw the line somewhere, why should the OP draw it here?
And before I get a load of grief, I'm not saying I wouldn't have shopped the guy, I would have. I'm just saying that its unfair to judge the OP by your own moral standards - unless you really would turn in your own mum...
Burgle the house while they are out. That'll TEACH 'em.
Ummm, ring the police?
Well I suppose we're lucky your experience isn't representative then.
Decent people can make a bad system work, a decent system cannot make bad people decent.