Basuki Tjahaja Purnama, known as 'Ahok', is the governor of Jakarta and as a Chinese Christian, is Indonesia's most prominent ethnic minority politician.
He has been charged with blasphemy, which carries a prison sentence of up to five years, despite claims of a lack of credible evidence against him. He is also running for re-election on 15 February.
Ahok ran into trouble after he was accused of criticising the Qur'an in an election video however he says he was simply unpacking the verse which political opponents may use to discourage people from voting for him as a non-Muslim.
He was charged by police in November last year while his trial began in December.
Religious freedom charity Christian Solidarity Worldwide says the case is part of a broader attempt to undermine Freedom of Religion or Belief in Indonesia.
CSW's East Asia Team Leader Benedict Rogers said: "Indonesia's blasphemy laws have long been a cause of injustice and division, and are misused for political reasons as well as religious intolerance to silence dissent, criticism or debate.
"They suffer from a very low threshold of requirements for evidence or proof of intent.
"We believe that the blasphemy case against him is without basis and politically motivated in order to prevent his re-election in two weeks' time, and also an indication of rising religious intolerance in the world's largest Muslim-majority nation.
"We call on the court to acquit Ahok."