(CN) – Spain’s judiciary, which critics say is too cozy with the country’s dominant political parties, will come under intense scrutiny in the coming months as its high court holds a politically explosive trial of Catalan independence leaders accused of rebellion and sedition.

The historic Madrid trial in the Supreme Court of Spain is expected to start on Feb. 5, or perhaps later, and last about three months, gathering testimony from hundreds of witnesses and experts. A ruling is expected in August, according to El País, a Spanish newspaper.

Demonstrators hold an ‘estelada’, the pro-independence Catalan flag, in Barcelona on Dec. 3, 2017. (AP Photo/Manu Fernandez)

In all, 12 leaders involved in the Catalan parliament’s failed, and illegal, drive in 2017 to declare Catalonia an independent nation will go on trial. They face charges of rebellion, sedition and misuse of public funds and sentences as long as 25 years.

“A guilty sentence would be remarkable, but it is possible, I am not ruling it out,” Emmy Eklundh, a lecturer in Spanish and international politics at King’s College London, said in a telephone interview with Courthouse News.

“If they find them guilty, it will have large repercussions for the future relationship between Spain and Catalonia,” she said. Conversely, a not guilty verdict “could repair relations and turn a new leaf,” she added.

The decision by prosecutors to file charges of rebellion has caused the most controversy. Under Spanish law, a charge of rebellion implies the use of violence or the threat of it. But the Catalan independence movement has been described as largely nonviolent.

Andrew Dowling, a Spanish history lecturer at Cardiff University in Wales, said the last time anyone faced a rebellion charge in Spain was related to a failed 1981 military coup d’état when members of the Congress of Deputies, Spain’s lower house, were held hostage for nearly a day and tanks surrounded the port city of Valencia.

“It will require some legal gymnastics to justify” the rebellion charges against the Catalan leaders, Dowling said in a telephone interview.

The unilateral declaration of independence by Catalonia followed a referendum on Oct. 1, 2017, an act Spain’s Constitutional Court ruled illegal.

The Spanish government sent in thousands of police officers to break up the referendum by storming polling stations and violently stopping people from casting ballots. In the aftermath, authorities arrested the independence leaders.

Now, more than a year later, their trial is giving rise to new questions about Spain’s treatment of the Catalan leaders – nine have been held for months in pre-trial detention – and whether the nation’s judiciary can be trusted to be impartial, fair and free of political influence.

Many people in Spain feel that the judicial system lacks legitimacy, in large part due to judicial scandals that have left people viewing the courts as stocked with judges too closely aligned with Spain’s dominant parties – the conservative People’s Party and, to a much lesser extent, the Spanish Socialist Workers’ Party.

In the case of Catalonia, this matters because both major parties are opposed to the region’s independence movement.

The legislative and executive branches of government – i.e., politicians – pick judges who sit on the Constitutional Court, the same court which ruled Catalonia’s independence referendum illegal. The legislative branch also picks members of the General Council of the Judiciary, a body that appoints judges to the Supreme Court.

Dowling blamed the People’s Party, long tainted by corruption scandals, for eroding the judiciary’s independence during its recent tenure in power by appointing judges “who are loyal to the party.”

The history lecturer said the party tried to ensure favorable judges oversaw corruption cases involving its members.

“There is explicit evidence of tampering with the independence of the Spanish judiciary to try to find favorable judges,” he said.

This fuels allegations that it will not be a fair trial and the defendants will end up convicted regardless of the evidence.

“Unfortunately, it is quite probable that the decision has already been taken and the prisoners will be condemned to many years in jail,” said Aleix Sarri Camargo, the international affairs coordinator for Catalonia’s government, in a recent opinion piece for Euronews, a news television channel.

The Catalan leaders argue charges should not have been brought for staging the referendum, and view themselves as victims of political persecution.

“In a democracy, no one should end up in jail for putting out ballot boxes,” said Oriol Junqueras, the former vice president of Catalonia, in a recent prison interview with Politico. Junqueras has spent 14 months in pre-trial detention. He contends the trial will not be fair.

Amnesty International and many legal scholars have called on Spain to drop the charges and release the defendants held in prison awaiting trial.

Pro-independence Catalans draw comparisons between their cause and the great civil rights struggles of the past over women’s suffrage, decolonization, the fight against apartheid and the gay rights movement.

There is, however, a major difference: Catalonia and its capital, Barcelona, cannot be said to be suffering from grave injustices. In fact, Catalonia is one of Spain’s most prosperous regions and its grievances have more to do with a sense of being culturally devalued and its coffers robbed by Spain’s central government in Madrid.

Still, the Catalan nationalist movement has won many supporters around the world – among them Noam Chomsky, a well-known American linguist and political activist. The defense wants Chomsky to appear as an expert in the trial.

In a statement last week, PEN International, a group that supports writers, called on Spain to release Jordi Sanchez and Jordi Cuixart, leaders of two pro-Catalan cultural groups who have been held in prison since October 2017 for their roles in the independence drive. Both men are writers and have become symbols of injustice to their supporters. They recently went on a hunger strike to draw attention to their plight.

“The Spanish authorities should drop the disproportionate charges of rebellion and sedition against Jordi Sanchez and Jordi Cuixart and release them immediately,” PEN said.

Spanish authorities dismiss allegations that the judiciary is not independent. In an email on Monday, the Supreme Court press office said the judiciary is independent of politics. As proof of that, the press office pointed to convictions through Spanish courts of Rodrigo Rato, a former deputy prime minister, and others involved with the People’s Party on corruption charges. Those convictions led to the fall last year of a government led by the People’s Party.

Across Spain, many people are opposed to the Catalan independence movement, and they equate the referendum and declaration of independence to a coup. Thus, many Spaniards are eager to see the secessionists tried in court.

Among Catalans, opinions are split over the question of secession and polls have shown a majority of residents do not want Catalonia to become a separate nation. The region enjoys a lot of autonomy and its population is made up of many people from other Spanish regions.

For their part, Spanish authorities say the charges are appropriate. The national prosecutor’s office charged in an indictment that the Calatan secessionists sought to “force the state to accept the separation of that territory, a goal that they nearly attained.” They also charge that the independence leaders were prepared to use violence to reach their goal.

During the trial, police officers sent in to shut down the referendum vote are expected to testify that they were injured in clashes with voters. The defense is likely to argue that police were the only ones to commit violence.

With so much doubt hanging over how fair the trial will be, lawyers and human rights advocates are gearing up to monitor the proceedings.

Amnesty International has requested the Supreme Court to allow it to act as international observers. Also, a consortium calling itself the International Trial Watch-Catalan Referendum Case is preparing to keep an eye on the trial.

“I think it will have to be a fair trial, in one sense because the eyes of the world will be on it,” Dowling said. “It won’t be a show trial. The basic problem is whether the charges are justified.”

The high court’s verdicts may eventually wind up on appeal before the European Court of Justice and also the European Court of Human Rights.

Guilty verdicts could also be put aside through pardons, Dowling said.

(Courthouse News reporter Cain Burdeau is based in the European Union.)