Is there a law that makes a higher than 50% result on referendum binding?

Question

As lots of reports/polls, one here talking about a shift in the general opinion on Brexit, where currently it is speculated that the public are Anti-Brexit, I find it bizarre that the UK decided to leave the EU on almost 50/50 split, considering the majority who voted leave are old people won't live long to experience it, and the majority who voted remain are young generations who would be the most affected by it.

Is there a law that makes a higher than 50% result on referendum binding?

If there is, why not a 66/33 minimum split (two-thirds) to make sure that the general opinion is truly solid on Brexit (or any other matter), rather than risking doing a Brexit when people don't want it anymore.

Answer 1

Assuming Wikipedia isn't far from the truth in the very first paragraph on the topic:

National referendums can be permitted by an Act of Parliament and regulated through the Political Parties, Elections and Referendums Act 2000, but they are by tradition extremely rare due to the principle of parliamentary sovereignty meaning that they cannot be constitutionally binding on either the Government or Parliament, although they usually have a persuasive political effect.

So no referendums can be truly legally binding in the UK (at national level)... unless the UK's party unwritten constitutional arrangements get a substantially different interpretation.

Or at least that's the received wisdom. As far as I can tell from reading the Act authorizing the AV referendum, that one was binding basically... and had simple majority specified as well, but Parliament could have still changed its mind later and could have (in theory) abrogated that law (although it didn't).

The Minister must make an order bringing into force section 9, Schedule 10 and Part 1 of Schedule 12 (“the alternative vote provisions”) if—

(a) more votes are cast in the referendum in favour of the answer “Yes” than in favour of the answer “No”, and

(b) [impenetrable legalese about some Order]

(2) If more votes are not cast in the referendum in favour of the answer “Yes” than in favour of the answer “No”, the Minister must make an order repealing the alternative vote provisions.

FullFact comments on that one

A UK referendum will only have the force of law if the Act setting it up says so. In practical terms this would mean someone would be able to go to court to make the government implement the result. The Alternative Vote referendum in 2011, for example, was legally binding in this way.

So, no there's no general law like you ask, but there is one example of a previous UK referendums that was "more binding" than the Brexit one; it also had the majority rule specified in the Act authorizing it (unlike the Brexit one).

As for why the UK isn't doing something else entirely... well that would involve a lot of speculation. Perhaps the "first past the post" political culture (see rejection of AV) extends to referendums.

Answer 2

Is there a law that makes a higher than 50% result on referendum binding?

No, no such law exists. Each UK referendum is set up by an Act of Parliament, and can have whatever rules Parliament wishes attached to it.

In the case of the EU referendum, it was legally only an advisory referendum, but successive Prime Ministers have pledged to obey its conclusions, and have not seen fit to retract or modify that promise. Their reasons for doing that verge on being opinion-based, but I believe this answer to be factual.

Answer 3

So my question, why didn't the referendum require a 66/33 minimum split (two-thirds) to make sure that the general opinion is truly solid on Brexit, rather than risking doing a Brexit when people don't want it anymore.

The referendum was advisory, it wasn't binding. UK politicians, in particular, the UK parliament, voted after the referendum to go ahead with Brexit. They voted for triggering article 50 to start the process of leaving the EU.

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Newer question:

In general. I am using Brexit as an example as if there is such law, it has really caused problem here

Yes, there exists at least one such referendum on the island of Ireland which includes Northern Ireland (which is part of the UK). The referendum is called a borer poll which exists per the Good Friday Agreement. From the the Institute of Government:

A border poll is the term for a referendum on Irish reunification. This would take place simultaneously in both the Republic of Ireland and Northern Ireland.

[...]

If both Northern Ireland and the Republic of Ireland voted in favour of reunification, the Good Friday Agreement further specifies that "it will be a binding obligation on both Governments to introduce and support in their respective Parliaments legislation to give effect to that wish."