The campaign against the proposed constitutional changes has been outgunned by the Yes, which can count on the resources of President Recep Tayyip Erdogan’s Justice and Development Party, the AKP, and its influence in government.
The HDP’s charismatic leader Selahattin Demirtas might have spearheaded the opposition. But he has been in jail since November last year, accused of links with the PKK.
Speaking at the party’s headquarters in Diyarbakir, in the Kurdish-majority south-east, Uca pointed out that Demirtas is not the only HDP member imprisoned under a government clampdown following last July’s failed coup.
“We are holding a referendum during a state of emergency, so we are facing many difficulties,” she said. “Thirteen MPs are in prison, two of them are our party leaders; 83 mayors are in prison today. But, despite all these difficulties, we are trying to struggle for the freedom of the people of this country. Just today dozens of our comrades involved in the campaign were arrested.”
The latest wave of arrests – 177 in all – came after the government declared that an explosion at Diyarbakir’s main police station on Tuesday was a “terror attack” and not, as first thought, an accident.
So the HDP’s relationship with the PKK is under the spotlight again.
While renouncing violence itself, the party does not hide its sympathy for the guerrillas, who enjoy considerable support among Kurds.
Indeed, Uca is speaking while seated among a group of hunger strikers – the families of PKK prisoners protesting at prison conditions, including alleged torture.
Like the families, she is sporting a vest bearing the picture of jailed PKK leader Abdullah Ocalan, and points out that one of the demands is an end to Ocalan’s five-year solitary confinement.
The peace process with the PKK, broken off after the AKP failed to win an outright majority in the first of 2015’s general election, should be revived, she says, and Ocalan should have a principal role in it.
“Today who is fighting Islamic State? It’s PKK. Today who are giving their lives for the people? It’s PKK,” she argues. “We can’t find a solution while we’re sending the PKK away from the table. We have to all get around the table to find a solution.”
The HDP opposes the concentration of power in the president’s hands proposed by the Yes camp.
“The president will be able to pick the ministers, the vice-presidents and even the MPs,” she claims, since he will choose the candidates for his own party, although she concedes he will not do so for the opposition.
But the party does want changes to the present constitution, which was adopted after a military coup in 1982.
“The constitution talks of one state and one language but in this country there are dozens of different cultures, religions, beliefs,” Uca points out. “We want a constitution where women’s voices are heard, where young people’s voices are heard, that will improve the environment, the economy. We want a constitution that is multicultural, multilingual and multireligious because in this country there are Kurds, there are [largely Christian] Armenians, there are Arabs, there are [largely Christian] Assyrians.”
Above all, the HDP believes a No vote will be a setback for Erdogan and an opportunity to end the conflict in the south-east, Uca says.
“A No vote will be another chance for peace,” Uca believes. “A No will be a chance for a new constitution, which everybody knows is necessary. The referendum will decide the destiny of all the peoples in Turkey. Erdogan is the one who walked away from the table in the peace process. He’s the one who said the peace process was frozen. Two weeks ago in the centre of Diyarbakir he again talked about ‘one nation, one language’, which again rejects the Kurds.”
The Yes campaign argues that approval of the changes would mean a strong and prosperous Turkey that walks tall on the world stage.
The No vote says it would be a step towards one-man rule and deepen the conflicts in Turkish society.
Whichever side you believe, the stakes are high in Sunday’s vote.
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