Never allow a single person to make any decisions, but instead have all decisions made by some set of representatives which are shuffled every now and them. To guarantee a majority decision, always use odd number of representatives.
Bonus principle: after every term let's select by random 50% of the representatives for the next term so the system may also utilize experience to certain degree (hopefully healthy degree).
TV-series I've recently enjoyed:
Marvels Agents of S.H.I.E.L.D.