Directors are elected by the membership to represent the best interests of the members. The plan is that the directors will do the research, debate, consider and then ultimately make the best decisions. The members do not need to do this heavy lifting. When then, do we ask the entire membership what to do? In what circumstances do we have a referendum where we ask every member?
The decision about Brexit, made by the voters of Britain could be a case in point. The economic analysis about the effect of leaving the European Union was complicated. Was an understanding of the ramifications beyond the skills and interest of the population? Does your group have a policy about the situation that would cause the board to want to ask the memberships what to do?