The lawyer for an Iranian Christian pastor, sentenced to death for renouncing the Muslim religion, says he hopes an appeals court will set his client free.

Attorney Mohammad Ali Dadkhah said Thursday he thinks there is a “95 percent chance” of acquittal for Youcef Nadarkhani, who appeared in court this week.

The 32-year-old converted to Christianity at the age of 19 and became a pastor of a 400-person Church of Iran congregation in the northern city of Rasht.

He was arrested in 2009 and sentenced to death after the court convicted him of apostasy, or abandoning his Muslim faith.

The death sentence has fueled an international uproar. Rights groups have demanded Iran free the pastor, and the International Campaign for Human Rights in Iran has called the conviction a “low point” for the Iranian judicial system.

On Wednesday, U.S. Speaker of the House John Boehner urged Iran to spare Nadarkhani's life and permit an “unconditional release.”