I hope you are NOT kidding around with a subject like this.
Kidding? Why no. It's no different than if someone had put "Court documents show parents, uncle had role in death - sick stoned freaks of the day", I am sure many, many people would post, saying things like "Well, they wouldn't have done this if they weren't smoking pot, or crack, or whatever." I am frequently appalled at how many crimes posted on this site involve alcohol, but no one ever says to ban it. So I do - ban alcohol and this crime wouldn't have happened.
Not to excuse them of course - they deserve to be locked up for the rest of their lives. Hopefully we won't have to release them from jail though, to make room for some druggie - or drunkard, if I was to get my way.