Mehrnehad was a reporter for the Tehran-based newspaper "Mardomsalari" and ran the Voice of Justice charity, which focused on childhood education in the southeastern province of Sistan-Baluchistan. An ethnic Baluchi, he was accused of being involved with the armed Baluchi militant group Jundullah, which has been blamed for bombings and attacks on government and police structures in the region.
Mehrnehad was reportedly arrested at the end of April 2007 at a question-and-answer session with local officials in Zahedan, at which he had confronted officials over their performance. He had also previously criticized local officials in an article posted to his blog.
According to Iran's International Campaign for Human Rights, Mehrnehad was detained by Intelligence Ministry agents, and a confession was extracted by torture. His trial was held behind closed doors on December 25, 2007, and he was sentenced to death on February 7.