It's hard to avoid reading about David Bain in the news. And to add to all the comments, here's a bit more.
There are two things that strike me as odd about the case. Firstly, the motive. While David's father might have had a motive, why would he have killed all his family apart from David? Surely there was no reason to kill his younger son, Stephen, nor his older daughter, Aroha, if his concerns were about his relationship with his other daughter, Laniet. To go round destroying all the family seems an insanity.
Even more unlikely is any motive in David's case. Here was a mild, quiet young man, a bit immature perhaps, but certainly not one who appeared to be greatly troubled by his dysfunctional family, if his behaviour in the world outside was anything to go by. Unlike other mass murderers, there was no hint of withdrawal from society, or underlying anger, or hatred of the world. Compare David to the young man who killed the students in Kansas. The two personalities are light years apart. And look at Bain when he came out of prison. Here was a man full of light and life. Certainly his pleasure at being released was huge, but wouldn't you think there'd be something else, a certain something you couldn't put your finger on? No sign of it. David Bain is either a very good actor, or he's innocent.
The other strange thing about this case is the fact that the police acquiesced in the burning down of the Bain house. This was done within a month of the murders. Apparently this was at the instigation of the Bain relatives. Doesn't this strike you as odd? There are two reasons why it's odd. Why would the police allow a major crime scene to be destroyed so early in the piece, and how come the family had the power to persuade them to do it? Note that the family have once again had a strong say in what should happen to David: he's not to be allowed to stay in the South Island. Says who?
It's crazy, but I have a suspicion there's someone else out there who knows a whole lot more about these murders. Someone who has sat in hiding for all these years, and has the guilt of five deaths on his or her head. Someone who doesn't appear to have a motive because there's never been enough investigation for motive beyond the father and the son. That might make some sense of the puzzle.