I agree that the parents are not responsible for his actions...Some people are just sick (for a lack of better words). I think this country in the last decade or so has moved towards this dangerous precedent of there is always something or somebody else to blame besides the person who does the act...
"he was sexually or physically abused", "tv or music voilence influenced him", "the justice system failed him"...all excuses used all the time...
The parents did not buy the exposives, they did not plan this, and they certainly did not set it off...
I am a kid of divorce and was brought up a latchkey (spelling?) kid...according to these type of prevalent studies looking for places to blame I should be filled with rage, been in trouble with law since I lack constant supervision, grades should have been poor, etc.
My mom is a smoker and dad was an alcoholic...I should have an addition as well, right? Wrong.
I make my own choices...I can interpret right from wrong on my own...