Ardent Brexiteers were accused of strident and overblown rhetoric in the run-up to the June 23 referendum.

They stand accused of the same hyperbole in the wake of the High Court ruling that, if validated by the Supreme Court, would mean the Government would have to achieve the agreement of Parliament before triggering Article 50 and leaving the EU.

Let’s be clear. The High Court is not trying to “scupper” Brexit. Even the lead claimant in the case Gina Miller accepts the referendum result. Brexit will happen.

So the hypocrisy beneath those shouting down this ruling is breath-taking. The Brexiteers campaigned for years to make Parliament sovereign – and now they shout down a court for reinforcing that very pillar of the constitution.

The High Court was not ruling on the merits of Brexit, nor was it ruling on the outcome of Brexit. It was ruling on the scope of British freedoms, the kind of freedoms to which the Brexiteers would normally raise their warm pints.

It ruled that the executive – the Government – did not have the right to undo domestic law using ancient Crown prerogatives that bypassed the will of Parliament.

These Crown – or royal – prerogatives have been used in the past for controversial decisions – such as going to war – but they have fallen into disuse because of the outcry that followed. Even Prime Minister Tony Blair put the Iraq War to a vote saying he couldn’t conceive of action using these unilateral powers.

Is it right, therefore, that these medieval conventions are now used to make the most momentous decision in recent British history?

Approached from the opposite angle, this ruling is not only welcome – but essential. It would be terrifying to think of the alternative.

Prime Minister Theresa May

Theresa May is Prime Minister only because she was still standing when an internal party crisis occurred. Without this ruling, she would possess the power to trigger the biggest constitutional upheaval in a generation without reference to any of the checks and balances that a democracy requires and without popular mandate.

If the ruling went the other way, it is conceivable she could use the Crown prerogative to override any piece of domestic legislation (for EU membership is underpinned by British law).

What if other aspect of law didn’t take the PM’s fancy? The Dangerous Dogs Act perhaps? Some fiddling with tax or immigration? Changes to criminal law to help a constituent or donor?

Read the judgment in full

Unlikely perhaps. But imagine another world in it wasn’t a strait-laced Theresa May figure who emerged from a party squabble to rule the country. Imagine it was a Donald Trump figure who found he was suddenly unfettered from the processes and obligations of democracy. The Crown prerogative is the perfect tool of tyrants.

High Court justices understand their role. By convention, they do not seek conflict with the elected Parliament and attempt to make accommodations and raise red flags to avoid court-made law.

However, there comes a time when an overbearing, overreaching, overstepping executive must be confronted with the rule of law and the people, through Parliament, allowed to have their say to curb.

The High Court has allowed this. It’s just what Brexit was all about.