The European Court of Human Rights has ruled that Switzerland violated the Turkish nationalist Doğu Perinçek’s right to free speech when it fined him for denying the 1915 Armenian genocide in a 2005 speech.
Perinçek, who was the head of the left-wing Turkish Workers' Party, was found guilty of racial discrimination in 2007 after he called the genocide "an international lie" during a public speech in the city of Lausanne.
The Armenians say Ottoman Turks slaughtered up to 1.8 million Armenians in a planned genocide between 1915 and 1918. Turkey denies the mass killings were genocide, saying the death toll is inflated.
In 2007, the Federal Court took the view that the facts of the 1915 Armenian genocide were common knowledge and that, therefore, Perinçek’s denial of those facts was driven by racist and nationalist motives.
Under the Swiss penal code any act of denying, belittling or justifying genocide is a violation of the country's anti-racism legislation.
Perinçek brought his case to the European Court of Human Rights, which ruled on Tuesday that Switzerland had acted in violation of Article 10 of the European Convention of Human Rights in its conviction. That article guarantees the right to free speech.
The Court of Human Rights also said it doubted there was as wide of a consensus on the Armenian genocide as the Federal Court had indicated in its ruling, pointing out that only 20 of the world's 190 countries had recognised the genocide.
The Armenian question has long affected relations between Switzerland and Turkey, including the postponing of official visits.
The House of Representatives recognised the Armenian massacre as genocide in 2003, but neither the Senate nor the cabinet has officially done so.
Switzerland has three months to appeal the Court of Human Rights' verdict.
swissinfo.ch and agencies