Volunteers with the Catalan National Assembly (ANC), the largest Catalan independence platform, have their hands full. They are distributing masses of neon yellow t-shirts and colorful buttons sporting a "Si" in favor of independence to be worn to the mass demonstration on September 11, the Catalan national holiday known as "Diada." Every year since 2012, hundreds of thousands have demonstrated for their autonomous region to become its own country. This year, the participants want to set up two main streets in Barcelona to form a large "x" symbolizing a mark for "Si" on the ballot.

The rally is taking place amid preparations for a planned independence referendum. On October 1, the region in the northeast of Spain wants to vote on its own state in an election which the central government in Madrid considers illegal.

Against the bitter resistance of the opposition and the Spanish central government, the Catalan parliament on Wednesday forced through a corresponding law — which the Spanish Constitutional Court shortly thereafter suspended in an expedited case. Still, the positive enthusiasm among pro-independence supporters is palpable.

"It was a very exciting moment," says Jaume Angerri, who had just bought the neon T-shirts for himself and his wife. "We are now faced with a fundamental change and are setting the course for our future." Finally, politicians are following the mandate of the people and creating facts on the ground, he added.

Harsh reaction from Madrid

The mood has relaxed among the pro-independence supporters, despite the state crisis that the debate has triggered in the meantime — and despite the consequences threatened by the political higher-ups. The Spanish prosecutor wants the police to stop all preparations and is threatening lawsuits on the grounds of disobedience, misuse of office and waste of public funds, all of which are punishable by imprisonment under Spanish law. The regional government is defiant. "We will face the tsunami of lawsuits and trials with a tsunami of democracy," said Catalan President Carles Puigdemont after the harsh words from Madrid.

The independence movement in the prosperous Mediterranean region has been growing for years. In addition to the hope that it would be more successful without transfer payments to poorer Spanish areas, emotional reasons play an important role. Many Catalans feel they lack recognition of their own culture and language, and separatists do not feel that Madrid takes them seriously in political terms.

Civil resistance

On Catalan television, ads continue to campaign for the referendum, and the preparations continue off-screen as well. In the 24 hours that elapsed between the adoption of the law and its suspension by the Constitutional Court, 16,000 volunteers registered and 560 municipalities have assured the Catalan premier of their support. They want to prepare and carry out the referendum, even if they are prosecuted for it.

"It is almost impossible to prevent the opening of polling stations and electoral elections on October 1," said constitutional lawyer Xavier Arbos. To this end, Spain's security forces would actually have to block access to the polling stations on election day, and if necessary, to confiscate ballot boxes. "It would be a very ugly image before the world, which Spain would certainly want to avoid," Arbos believes. He and other lawyers have considerable doubts about the legal validity of the public inquiry.

Doubts about validity

The referendum bases itself on a peoples' right to self-determination. According to established jurisprudence, however, this applies exclusively to former colonies or ethnic groups in which people are suppressed because of their ethnicity or ethnic affiliation. As a unilaterally initiated vote outside the legal framework, it also fails to meet the prerequisites for referendums set out by the Venice Commission, a Council of Europe body that advises on constitutional law.

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The Catalan regional government, however, has taken little heed of the legal concerns. It has announced that if the outcome of the referendum favors a split from Spain, independence will be announced two days later. International reactions to the results are immensely important — a fact not lost upon Catalonian leaders. This can also be felt in the run-up to the Diada.

At the Assembly's counter, a volunteer shows a woman the location on a map where she and her friends will stand on Monday to form the symbolic ballot "x" on the streets of Barcelona. "We must show the world that we have been a democratic movement since the start, and a peaceful one too," she says, reaching into the box with the colorful "Si" buttons. "Only that way can we hope for their support."