The Government won the election and put a Bill before Parliament for a non-binding referendum. Being non-binding, there was no need to define a majority or supermajority; had the vote been binding, a majority or supermajority definition would clearly have been required. Had this issue been debated, it can be argued that a supermajority of 60 or 66% might have been considered appropriate for a major constitutional change. But no such debate took place, as the vote was not intended to be binding.
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