sn't there an argument that in this case, The FO commited suicide he didn't actually murder the PAX. His actions may have led to the death of 150 people but he would have disassociated himself from that.
After all he waited until the captain was out of the FD. He didn't grab the AXE and kill him personally.
If the voice recordings are accurate and the girlfriend statements too this would appear to be a pre meditated murder, thought out and coldly planned awaiting the right time which would mean also thought out over the loss of life his actions would cause.
very different to an on the spur of the moment action by an individual flipping and not considering the outcome on others in his care