I think all murderers have damage in some way- some are "bad seeds", born that way, and some have "learned" behaviors from a life of abuse. (I'm not talking about murderers that are defending themselves tho'- that's different, IMO).
Stopping them??? I don't know if you can stop the "bad seed" murderers- medication, castration...?? Will they take their meds on their own? Probably not. Will they accept castration?? Is this moral, some will say?? Since these "bad seed" murderers don't feel what others feel, how can they change? They have no empathy- they were born that way- missing something crucial to be a moral person, IMO.
The murderers who have had an abusive upbringing- I think these people may be able to get some help to overcome their childhood abuse.
Nature/nurture???? Can children learn empathy if they don't have that capacity? Some say yes- some say no. I say yes, in a way- empathy can be "mimicked', but if push come to shove, the "bad seed" will always be there, IMO.
All..:moo: