This is a mess that could have been avoided.
In 2015 the UK Parliament passed a 64-page law establishing that "A referendum is to be held on whether the United Kingdom should remain a member of the European Union."
Nowhere in those 64 pages did it say what would happen should the referendum actually go for Brexit.
Maybe nobody thought it would. Maybe the government was hoping for an escape hatch should it be a squeaker.
It's possible, as is the way with these things, that it was a screw-up.
But now the Supreme Court has recognised what most sensible legal experts always said was the case: that over the four decades of EU membership the ties are too tight to be cut by a simple statement by a minister of the Crown.
Parliament has, over the years, incorporated a lot of European law into British law, conferring rights to British citizens in the process.
Only Parliament can take those rights away and make such a now-fundamental change to the constitution.
So the government needs to get an Article 50 Brexit trigger through both houses of Parliament, one of which it controls, and the other of which is bound by tradition not to cause too much trouble.
Simple? Probably, but not necessarily.
There are people in both houses who now have the opportunity, and probably the will, to cause the government a lot of grief.
They can try to attach riders, influencing the flavour of Brexit that Britain ends up with.
They could try to impose a timetable, or new obligations of transparency on the government during Brexit negotiations.
They can pull hard on the handbrake.
And while the Conservative majority Commons will probably add more hot air than substance, the House of Lords is firmly packed with Remainers who could really jam up the process until they get what they want – and can't be threatened with an election should the whole thing grind to a halt.
This, of, course, is how British democracy works.
Those who attacked the High Court will now probably also attack the Supreme Court, a bunch of eight unelected judges who have defied the will of a majority of British people.
This is nonsense. They haven't blocked Brexit, they've just ruled on the proper way to do things.
This is a parliamentary democracy, not an Athenian town square. Laws are passed by members of parliament, not by decree or mob vote.
You can debate which system might work better, but you can't deny it's the system we have.
It's many centuries since anyone tried to argue that the Queen's ministers can arbitrarily bypass the representatives of the people.
Now they're going to have to deal with them.
