You're considered an adult when you're 11 years old

In Pennsylvania, that is.  Is this to set an example for all 11 year olds?  Read this. Kids should know better than to go around shooting people with shotguns, but what purpose will trying them as adults serve?  13, 14, 15- maybe (teenagers).  But 11?  Seems whacky to me.  I can't imagine the kid being convicted with anything more than involuntary manslaughter.   Of course they argue that he is unlikely to be rehabbed in juvie, but I'm still saying that 11 is a tad bit young for being tried as an adult.