Romney's Willie Horton?

http://www.bostonherald.com/news/regional/general/view.bg?articleid=1046152

They were talking about this case on Howie Carr today. Most of the fingers that were being pointed were pointed at the judge for releasing the guy on his own personal recognizance.
I wanted to call and ask two questions about this:
1). The guy was released after serving 16 years for manslaughter for what sounded like a rather brutal beating death of his mother. If that crime was as bad as it sounded, why was it just manslaughter? Why not first or second-degree murder and shouldn't the prosecutor be at fault for not trying to get the murder conviction?
2). They took issue with the bail thing, but isn't it true that the purpose of bail is to make sure the defendant shows up for his trial and has nothing to do with protecting the public from the defendant?
To me, if you're going to blame somebody, blame the prosecutor who couldn't get the guy put away for life.