Thankx srax - but how do you get to murder? DNA evidence will point to rape/assault - what else do they have that moves from rape on to murder? Large amounts of blood, brain matter, or murder weapon would lead to that (sorry for the graphic words).
As for the RSO's - ITA something has to be done. I started a thread in the "crimes in the news" forum the other day. We had a convicted child rapist/killer living in one of our parks downtown and it seems LE was quite unaware of it - until the local paper broke the story. Now they have arrested the guy "to get him help" - YEP! HELP - he's a vet so the VA hospital is going to give him a bed.
I did a search for RSO's in my neck of the woods. Within 5 miles of my house I have 597 of them!!!!

Yep - and some are just listed as transient - when they do that all they have to give is the streets and cross-streets that they "hang around" on.
I like the idea of "chipping" them. And actually I can kinda see this might be possible - legally. We all know something has to be done.