Robin and Margaret Bain and three of their four children – Arawa, Laniet and Stephen – were killed by gunshot in Dunedin, New Zealand, on 20 June 1994. The only suspects were David Cullen Bain, the eldest son and Robin Bain, the father.

Here is the link to the article we mention in the episode:

https://medium.com/@sesrenaconference/david-bain-and-the-black-hands-ce6e5f5a0df6