Legislate that all UK future constitutional referenda (like Brexit & Scotlands Independence ref) must have a super majority of at least 60% to effect change. Furthermore there should be a minimum 75% turnout. Enacting this legislation would ensure there was a clear irrefutable majority for change.
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The purpose of the change is to embed the principle of a real and unarguable will for change in law & the constitution. Both recent UK referendums has caused untold division within society & has caused attention post these referendums to be focused on that division rather than than more critical & essential matters of state & local politics.