Editors Note: On October 27, the Catalan regional parliament voted 70-10 to declare independence from Spain. This comes after the Spanish government attempted to stop the independence referendum, in which 90% of the Catalans who voted favored independence. In this article, Prof. Sorens examines the legality and morality of secession.

A large region of Spain called Catalonia has announced October 1 as the date of a binding referendum on its independence from Spain. This is the culmination of eight years of independence activism, regional elections, and public consultation. The Spanish government says the referendum is illegal; the Spanish Constitution declares Spain to be “indivisible.” If the referendum vote succeeds, should Spain allow Catalonia to secede? And if the Spanish government forbids it, how should other governments respond?

Protecting Citizens’ Rights

The first way to think about these questions is to see which course of action better protects citizens’ rights. Suppose first that the Catalan government will be roughly as respectful of citizens’ rights and liberties as the Spanish government is. (Independentists argue that it will be more respectful; unionists dispute this.) In that case, we can focus narrowly on the right to live under a government of one’s own choosing.
People don’t talk about this right much, but it’s extremely important. If you live in a Western country, your government disposes of 40–60% of your income, subjects you to thousands of criminal statutes, and regulates everything from your intimate family relations to your contracts in the marketplace. Your relationship with your government is, whether you like it or not, the most significant relationship in your life: no one else has the power or legal authority to put you in jail, after all. So why shouldn’t your relationship with your government be as consensual as possible?
Working from the premise that it is more just to allow people to live under a government they prefer, we can see the attraction of deciding controversies over sovereignty with a referendum. If more Catalans prefer to live under a Catalan state than wish to live under the Spanish state, then it is better to allow independence. If fewer do, then it is better to forbid it.

Defining the Threshold for Referendum Success

Some scholars have argued that independence referendums should have a greater than 50% plus one threshold for success. The motivating idea here seems to be that the rights of those inclined to oppose independence are more important than the rights of those inclined to support it — and this idea is not as implausible as it sounds. Independence could mean oppression of the minority. Protecting a greater number of people’s rights could involve violating more significant rights.
In the case of Catalonia and Spain, it is difficult to argue that Catalonia is likely to violate more rights than Spain does. (There is a pro-independence Marxist party in the Catalan Parliament, but there is also an even larger semi-Marxist party, Catalonia Yes We Can, that opposes independence, and there are also far more right-wing extremists in the anti-independence camp than in the pro-independence camp.) Moreover, the Catalan pro-independence coalition has said that after independence, all Catalan citizens will have the right to dual nationality, retaining their Spanish citizenship. This is an important move by the Catalan government because it reduces any legitimate reasons for those who oppose independence to complain about injustice.
Catalonia could go even further and allow its citizens to choose which government they will pay certain taxes to in exchange for eligibility for excludable services. By “excludable services,” I mean those that do not have to be provided for everyone in the territory, as defense, roads, and police do. Social welfare programs and education are examples of excludable services (“private goods” or “club goods” in the language of economics). If pro-Spanish Catalans are allowed to retain the Spanish link for these services, then there is all the more reason to concede a 50%-plus-one threshold for independence.

The Legality and Morality of Catalan Secession

Let’s look at some objections to the idea of secession.
First, what about the illegality of secession under the Spanish Constitution? Let’s be clear about what constitutions do and do not do.
Constitutions do not tell citizens what to do and impose penalties on those who don’t comply. Constitutions constrain and authorize government. They may authorize government to impose penalties on citizens, but they do not require it. “Indivisibility” may mean, at most, that government officials are prohibited from breaking up the country, but it does not mean that government officials must punish citizens who withdraw their consent from the state.
Catalonia has devised its independence process to allow for a citizen-led constituent assembly after a successful independence referendum. Legally speaking, there is no requirement for either the Catalan or Spanish governments to punish citizens who complete the independence process.
Second, under some circumstances, breaking the law is justifiable. If the law is unjust, and breaking the law would not threaten the rights of others or violate any moral duties toward oneself, then it is morally permissible to break the law. A law proclaiming the indivisibility of the state is an unjust law because it does not permit citizens to withhold or withdraw consent: it forces them to be subjected to a legal system to which they never agreed. Breaking even an unjust law shouldn’t be done casually, especially by government officials, because it could undermine public order. But if those risks to the rights of others are low enough, then it can be justified.

Upholding the Spanish Constitution

But what about the fact that over 90% of Catalans voted in favor of the Spanish Constitution in 1978, which contained the indivisibility clause? Many Catalans say they voted for the constitution under duress, because the alternative to the constitution was continued dictatorship. This is a valid point. But even if it had not been adopted under duress, there are two additional points to consider.
First, the Catalans who voted for the Spanish Constitution are largely not the same Catalans voting for independence now. A previous generation cannot bind a future generation. I should not be able to make political decisions now that will bind my daughter decades from now.
Second, a principle of common law that has a good basis in ethics is that you generally can’t require specific performance from a contract. If I sign a contract agreeing to work for you, and then back out, you can’t force me to do the work anyway — that would be slavery. What you can do is sue me for damages. A promise not to secede is like this. At most, breaking the promise would entail compensation for damages, but you can’t force someone to remain a part of your group — or your state — against their will.
In conclusion, the more Catalonia does to guarantee respect for the rights of all its citizens after independence, the more confident we can be that Catalonia’s independence should be recognized following a successful majority vote.