REBELLION. It is a crime which has lost its century. Sedition, treason, lèse-majesté – these are offences of a pre-democratic age, when dissent was the same as disloyalty, when the state struck out at its enemies through the courts. Or they ought to be.

This week, the King’s Theatre in Glasgow is staging Trial By Laughter. Written by Private Eye’s Ian Hislop and his collaborator Nick Newman, it is the story of William Hone. A London bookseller, Hone published scurrilous critiques of Britain’s rotten boroughs and its rotten Prince of Wales. He called out the venality of the plump Prince Regent’s ministers. He didn’t spare the ludicrousness of its electoral system either, or the self-seeking, humbug and the hypocrisies of Britain’s ruling classes.

And for these democratic excesses, a legal bullseye was affixed to his chest. The authorities summoned him to face three separate trials for seditious libel between the December 18 and December 20, 1817. On all three occasions, a jury of his peers threw out the state’s attempt to restrain free political expression and his right to ridicule the ridiculous and hold power to account.

In Madrid, by contrast, another court sat in terrible earnest this week. On Wednesday, the Spanish judicial authorities commenced their proceedings against twelve Catalan ministers and politicians on charges of violent rebellion arising from the failed 2017 independence referendum. They face up to 25 years in prison, if convicted.

The visuals were stark. The Tribunal Supremo is a formidable chunk of judicial architecture. Marble columns, ancient wood, gilded thrones – I was particularly struck by the exposed picture the 12 accused politicians cut, surrounded in the centre of the chamber. The courtroom is a tight horse-shoe which must make you feel scrutinised and exposed on all sides – though the defendants appear uncowed.

Declining to answer questions from the prosecutor, former Catalan vice-president Oriol Junqueras (pictured below) told the Supreme Court: “I consider myself a political prisoner. I will not renounce my democratic convictions.”

The National: Oriol Junqueras refused to rule himself out as a candidate

Remanded like murderers and dangers to the public, nine of the 12 accused have been incarcerated in pre-trial detention since 2017. This is just one of the many details illustrating the grossly disproportionate and authoritarian way the Spanish state has responded to this constitutional crisis.

So how could this happen? Isn’t self-determination enshrined in international law? Doesn’t the European Convention on Human Rights have anything to say about their situation? Supporters of Scottish independence tend to be enthusiasts about international law until they dig a bit more deeply into its limitations.

It is true, the UN charter recognises the right to self-determination. Both the International Covenant on Civil and Political Rights and International Covenant on Economic, Social and Cultural Rights enshrined the principle that “all peoples have the right of self-determination”. “By virtue of that right,” it says, “they freely determine their political status and freely pursue their economic, social and cultural development”. But people often trip up on the next step.

Some folk are inclined to define “self-determination” as meaning “becoming an independent country”. But this isn’t how the overwhelming majority of international lawyers understand the term. Voting in Westminster elections is a form of internal self-determination for Scots, as hollow as that participation often feels. More substantively, so too is the whole edifice of Scottish devolution, giving Scots scope for distinctive political expression within the limits of the Scotland Act. Secession, by contrast, represents a much more drastic remedy. And outside of colonial contexts or sustained oppression by an alien power, most international lawyers argue countries like Quebec, Scotland or Catalonia have no right in international law unilaterally to secede from Canada, the UK or Spain. But that can’t be the end of the argument in a supposedly liberal democracy faced with popular demands for greater autonomy. International law underpins the Spanish position, but it also illustrates its weakness. All the Spanish state can do is stand on their rights, and rely on the jackboots and the nightsticks of the Guardia Civil to defend their position. This is no statecraft. This is the sad ghost of a mature, free and representative democracy.

In 2010, the International Court of Justice (ICJ) reached its conclusions in the Kosovo case. In one corner, you had the Serbian state arguing – backed up by a slew of legal texts – that it was entitled to its territorial integrity. On the other, you had the institutions of the new Kosovo, arguing their declaration of independence was perfectly lawful in international law, and in any case, represented a kind of remedial secession against a legal regime which had long oppressed and excluded Kosovars from full and equal participation in government, accompanied by respect both for human rights and the rule of law. The judgment is rich with historical ironies.

Behind Serbia ranked Russia, who argued that their allies’ territorial integrity must be respected. In 2014, Vladimir Putin would ignore the same principle to annexe the Crimea. Also at their elbow in 2009 were the Spanish Government, arguing that Serbia’s territory must be protected. The UK Government took a line broadly sympathetic to the Kosovar argument. In the light of the tragedy and the oppression, it was too late – far too late – for the ICJ to pull the broken limbs of Serbia back together again.

Daniel Bethlehem QC, for the UK, told the Court that “Kosovo, for its part, has made it quite clear that, given the legacy of abuse, it cannot again become part of Serbia. Courts do not order estranged spouses to continue in a broken marriage”. The Spanish authorities should learn Bethlehem’s lesson.

This trial is, presumably, intended to be a show of strength – but like all defensive over-reactions, this case reeks of weakness and uncertainty. You can’t prosecute your way to national unity. Political ideas cannot be driven out of people’s heads by baton charges. Smash the ballot boxes, if you like. Batter pensioners exercising the franchise. Even suspend the parliament. You might achieve compliance, for a time. You may succeed in fostering fear and anxiety. But what kind of democracy thrives when its unity is achieved only through ramping up of coercive mechanisms of control? You have a people subdued, rather than one united in common civility. Riot police can’t quell a riot of ideas.

In the end, history often laughs at these strongmen. In 1793, the Scottish radical lawyer Thomas Muir faced trial for sedition in the High Court of Justiciary. Like Hone, Muir of Huntershill was no blood-drenched Jacobin. He was accused of attending a meeting in Kirkintilloch in which he “delivered speeches in which he seditiously endeavoured to represent the government as oppressive and tyrannical”. Worse, he circulated the works of Thomas Paine to print workers and weavers in Paisley. On the bench, Lord Justice Clerk Braxfield presided with dark relish and prejudice for the government’s side. Unlike William Hone, he was not acquitted.

Muir was condemned by a biased jury and transported to Australia. These were only the beginnings of his adventures, which ended with his death in France in 1799 aged 33, having lost half his face and having inadvertently circumnavigated the globe. But the words he uttered when Lord Braxfield unjustly condemned him are etched on to the living stone of the Martyr’s Monument, whose spike looms over Edinburgh from Calton Hill and still points accusingly at the statue of his ultimate destroyer – Henry Dundas, 1st Viscount Melville – who still stands, unabashed, in St Andrew’s Square. “I have devoted myself to the cause of the people,” Muir said. “It is a good cause – it shall ultimately prevail – it shall finally triumph.” He was right. Despite his best efforts, Dundas’s cold stone eyes look out over a democratic country. For the Catalan prisoners, encouragement – for Spain, perhaps, a lesson.