PETER A Russell (Letters, October 18) cleverly conceals the reality behind the convictions by Spain of politicians in Catalonia.

Mr Russell writes that the “written constitution that must be enforced if the rule of law is to be maintained”, which few would dispute, at least at first sight. However, no constitution is an act of God. I wonder if Mr Russell would defend the Weimar Constitution in Germany, as amended by the Nazis’ 1933 Enabling Act, allowing Hitler to enact laws without the the Reichstag’s involvement? A constitution is a political enactment, which might set out how the law operates at a particular time but is only ever provisional until political action requires it to change. For instance, the protests against the poll tax were often against the law, but were they wrong? Would Mr Russell prefer if the poll tax still applied?

The Spanish constitution is a child of the immediately post-Franco era, maintaining many Falangist precepts. Article 2 confirms the “indissoluble unity of the Spanish nation, the common and indivisible homeland of all Spaniards”. The words “indissoluble” and “indivisible” are, though, no less a political judgment than that Catalonia should be independent.

Moreover, they are problematic for any political movement whose aims include independence, as Article 6 notes that the formation and activities of political parties are free “within respect for the Constitution and the law”. This allows the Spanish government, and Mr Russell, to define Catalan independence movements as “unconstitutional” and thus “illegal”.

Article 92 grants the King a monopoly right to call referenda on constitutional matters, so the democratically elected government of Catalonia’s referendum was illegal. Yet it is obvious that the chances of the King of Spain granting the Catalans the right to call a referendum on their own future is vanishingly small at best.

If none of this looks familiar to a Scottish voter then they haven’t been paying attention, for just as the King of Spain has a monopoly on granting legal referenda in Spain, Westminster claims a monopoly on legal referenda on Scottish independence, via the list of Reserved Powers in the Scotland Act which includes constitutional matters. The need for a Section 30 Order means the difference between Scotland and Spain is uncomfortably less than one might have imagined, at least in legal terms.

The examples of Scotland and Catalonia bring into sharp focus the relative rights of a population to self-determination, and of a state to maintain its territorial integrity. But, what needs to be remembered is that this is a matter of political judgement and not one that can always, or easily, be settled by reference to the political document that is a constitution. As John Rawls wrote in Political Liberalism, citizens should “justify their opinions and deeds by reference to what they may suppose others could accept consistent with their freedom and equality”. When a constitution includes laws designed to maintain a political structure opposed by others can Rawls’s requirement be said to be satisfied?

Alasdair Galloway, Dumbarton.

AN Alternative History of the EU: What if the proposed Constitutional Treaty of the EU had been ratified by all its members? What if the subsequent Lisbon Treaty (the so-called Reform Treaty, though it did not go far enough) had not included an Article 50? How would the 30-year Tory civil war on EU membership have played out? Would David Cameron still have gone for his, presumably illegal, referendum? Would Boris Johnson, Nigel Farage, Michael Gove and fellow separatists been paraded before the EU Court of Justice (or perhaps under “subsidiarity” the UK Supreme Court), and sentenced to years in prison for their “crimes” of secession?

Very unlikely I would have thought. But instead of British nationalists supporting Spain’s police and judicial overreaction to a simple act of democracy, it might be better for the future wellbeing of Spain/Catalonia to insert the equivalent of an Article 50 in their constitution. The thuggish suppression of what many people see as a democratic right of self-determination will not help keep Spain as a united country. Discussion, and mutual respect toward the wishes of the complex plurinationalist communities of Spain might.

GR Weir, Ochiltree.