Basuki Tjahaja Purnama, popularly known as Ahok, the Christian and ethnic Chinese governor of Jakarta, recently went on trial for blasphemy for disputing an interpretation of the Koran. Few could have imagined that the governor's comments could result in a charge when he made them, but authorities have been pressured by hardline Muslim groups that have poured onto the streets of the capital in recent months. Rights campaigners say Ahok’s case illustrates growing concerns for freedom of speech. A programme prepared by Patrick Lovett.