A very useful round up of the pitfalls of group decision making and the ways in which they can be mitigated can be found here
https://royalsociety.org/topics-policy/publications/2018/making-better-decisions-in-groups/ and the full article https://royalsocietypublishing.org/doi/10.1098/rsos.170193#d3e1687
Part 3 Consider - On Power - What is Power and Where does it come from