After the UK asks for another extension or even leave the EU, is it possible for a person/organisation/group of people to go to court and argue that the difference in polls on the 2016 referendum was too small, and the polls after two years have now shifted towards staying in the EU, and ask the court to "force" a referendum on joining/staying in the EU?
- Courts have no role in determining how voters would vote today and if that is a reason for a re-election. Otherwise no matter can ever be settled, there is always the possibility of a repeat.
- If one were to question the accuracy of the count, one should have protested three years ago, with specifics as to the polling stations where fraud and miscounts are suspected.
- The referendum was legally not binding. It was merely the political decision of important actors to promise to honor it.
So having a court order another referendum (which I don't think it possible, anyway) would not help.
People could go to court and challenge the legitimacy of the 2016 referendum, for example on the grounds that one of the official parties spent too much money, or that there was a printing error on some ballot papers, or that one of the people counting the ballots was drunk. If such a challenge succeeded, it's not clear what remedy the court could order; it could try to order a re-run, but I doubt that would ever happen. Since Parliament is now treating the referendum result as purely advisory, the court would probably decide that no remedy was needed.
People could also, I guess, argue that the whole concept of leaving the European Union is some kind of breach of human rights and therefore not within the prerogative of the UK government, referendum or no referendum. Perhaps there's something in EU law that says once EU citizenship has been granted to an individual, a member state can't take it away. I doubt such a challenge would succeed, but who knows.
But your idea of arguing in court that the winning margin was too narrow or that opinions have changed since the vote was called wouldn't wash. Those are political arguments, not legal arguments.
A court can intervene in several ways. The main one would be a judicial review, where a court looks at the governments conduct and asks if it was an act that was both legal, and which a reasonable government could have reached by reasonably following the wording of the law.
For the Brexit referendum, you would have to show that
- Something in its execution was actually unlawful (breached UK or EU law), or was in some way an executive overreach, or
- The actual holding of the referendum, or something about the way it was held, was not a reasonable interpretation of the European Union Referendum Act 2015 (the law under which it happened) or some other relevant law.
No chance of that.
So you'd have to show that some other action was incorrect. Even a 1 vote majority would be enough for a court to conclude that endorsing the result was not an unreasonable decision. The rest is politics not law, so the courts won't intervene at all.
If you could identify some specific irregularity, and it may have materially affected the outcome or events, then a court might intervene to remedy it. Also if the events were likely to have been materially affected by something or other, in a manner that is likely to have introduced an unlawful element, then the court might rule accordingly.
But they won't do so just because some people feel the result is too close, or events aren't what were expected, or because some people may have changed their mind since then (however many polls show it). And in any event, they wouldn't "force" a second referendum as a solution. At most it would rule on the validity and procedure of the existing one, and perhaps issue some kind of ruling or injunction to prevent harm resulting from the invalid act.
The courts view, put simply, is that if the law wasn't followed, then something can be done. But if the law was followed, it's down to parliament and (moreso) the government - if they want to do anything different, they can, if not, the courts job is to see that the laws of the country have been followed, which they have, and that's the end of it.
Short answer - not a chance on this case. On another case, if the criteria are met, maybe.
A law court can only ever resolve questions of law.
The 2016 referendum was a straight in/out referendum so that one vote, either way, above 50% would be legally sufficient to win. Now, if you can argue (with evidence) that the vote wasn't legally fair then you could challenge the original result. But, even if it were struck down, it wouldn't follow that it would be rerun. That would be a political decision.
To have the courts opine on a second referendum would require there to be a law requiring a second referendum. That currently isn't the case. That's not to say it couldn't be though. For example, if Parliament had voted for a second referendum, and passed a bill confirming it, but the Government refused to enact it then the courts could (and likely would) be asked to step in.
It's also worth pointing out that it is unlikely, ever, that the result of an opinion poll (as against an actual poll) would have much legal weight. They are just a sample and usually not a large one at that. They use various statistical techniques to attempt to simulate real poll results but they are, famously, difficult to get right for rare events like UK referendums.