I had never heard of Matthew before today when I stumbled across it online. The article posted below is pretty extensive.
I know they have been questioning a former police officer recently in connection. Personally I think the crime looks like it was done by a teenager. There is something immature and childish about it. The dirt and sticks being stuff in his mouth, crushing his chest with the rock, no sexual molestation - it just reeks of a crime done by young boys or boy pumped full of testosterone who killed Matt just to kill him.