Wiki.

"The Supreme Leader of Iran is the head of state and highest ranking political and religious authority (above the President). The armed forces, judicial system, state television, and other key governmental organizations are under the control of the Supreme Leader. There have been only two Supreme Leaders since the founding of the Islamic Republic, and the current leader (Ali Khamenei), has been in power since 1989. His powers extend to issuing decrees and making final decisions on the economy, environment, foreign policy, education, national planning of population growth, the amount of transparency in elections in Iran, and who is to be fired and reinstated in the Presidential cabinet.

The Supreme Leader is appointed and supervised by the Assembly of Experts. However, all candidates to the Assembly of Experts, the President and the Majlis (Parliament), are selected by the Guardian Council, half of whose members are selected by the Supreme Leader of Iran. Also, all directly-elected members after the vetting process by the Guardian Council still have to be approved by the Supreme Leader. As such, the Assembly has never questioned the Supreme Leader."

Do read that second paragraph slowly. Not democracy.