Constitution of the Islamic Republic of Iran in the context of "December 1979 Iranian constitutional referendum"

The Jaʿfarī school, also known as the Jafarite school, Jaʿfarī fiqh (Arabic: الفقه الجعفري) or Ja'fari jurisprudence, is a prominent school of jurisprudence (fiqh) within Twelver and Ismaili (including Nizari) Shia Islam, named after the sixth Imam, Ja'far al-Sadiq. In Iran, Jaʽfari jurisprudence is enshrined in the constitution, shaping various aspects of governance, legislation, and judiciary in the country. In Lebanon, this school of jurispudence is also accounted for in the legal system of the country and Shia Muslims can call upon it for their legal disputes.

It differs from the predominant madhhabs of Sunni jurisprudence in its reliance on ijtihad, as well as on matters of inheritance, religious taxes, commerce, personal status, and the allowing of temporary marriage or mutʿa. Since 1959, Jaʿfari jurisprudence has been afforded the status of "fifth school" along with the four Sunni schools by Azhar University. In addition, it is one of the eight recognized madhhabs listed in the Amman Message of 2004 by King Abdullah II of Jordan, and since endorsed by Sadiq al-Mahdi, former Prime Minister of Sudan.

An entrenched clause or entrenchment clause of a constitution is a provision that makes certain amendments either more difficult or impossible to pass. Overriding an entrenched clause may require a supermajority, a referendum, or the consent of the minority party. The term eternity clause is used in a similar manner in the constitutions of Brazil, the Czech Republic, Germany, Greece, India, Iran, Italy, Morocco, Norway, and Turkey, but specifically applies to an entrenched clause that can never be overridden. However, if a constitution provides for a mechanism of its own abolition or replacement, like the German Basic Law does in Article 146, this by necessity provides a "back door" for getting rid of the "eternity clause", too.

Any amendment to a constitution that would not satisfy the prerequisites enshrined in a valid entrenched clause would lead to so-called "unconstitutional constitutional law"—that is, an amendment to constitutional law text that appears constitutional by its form, albeit unconstitutional due to the procedure used to enact it or due to the content of its provisions.

The Guardianship of the Islamic Jurist (Persian: ولایت فقیه, romanized: Velâyat-e Faqih, also Velayat-e Faghih; Arabic: وِلاَيَةُ ٱلْفَقِيهِ, romanized: Wilāyat al-Faqīh) is a concept in Twelver Shia Islamic law which holds that until the reappearance of the "infallible Imam" (sometime before Judgement Day), the religious and social affairs of the Muslim world should be administered by righteous Shi'i jurists (Faqīh).

Wilāyat al-Faqīh is associated in particular with Ruhollah Khomeini and the Islamic Republic of Iran. In a series of lectures in 1970, Khomeini advanced the idea of guardianship in its "absolute" form as rule of the state and society. This version of guardianship now forms the basis of the Constitution of the Islamic Republic of Iran, which calls for a Guardian Jurist (Vali-ye Faqih, Arabic: وَلِيٌ فَقِيهٌ, romanized: Waliyyun Faqīh), to serve as the Supreme Leader of that country. Currently, this role is held by Ayatollah Khamenei.

The supreme leader of Iran, also referred to as the supreme leader of the Islamic Revolution, but officially called the supreme leadership authority, is the head of state and the highest political and religious authority of Iran (above the president). The armed forces, judiciary, state radio and television, and other key government organizations such as the Guardian Council and Expediency Discernment Council are subject to the supreme leader. According to the constitution, the supreme leader delineates the general policies of the Islamic Republic (article 110), supervising the legislature, the judiciary, and the executive branches (article 57). The current lifetime officeholder, Ali Khamenei, has issued decrees and made the final decisions on the economy, the environment, foreign policy, education, national planning, and other aspects of governance in Iran. Khamenei also makes the final decisions on the amount of transparency in elections, and has dismissed and reinstated presidential cabinet appointees.

The office was established by the Constitution of Iran in 1979, pursuant to Ayatollah Ruhollah Khomeini's concept of the Guardianship of the Islamic Jurist, and is a lifetime appointment. Originally the constitution required the supreme leader to be Marja'-e taqlid, the highest-ranking cleric in the religious laws of Usuli Twelver Shia Islam. In 1989, however, the constitution was amended and simply asked for Islamic "scholarship" to allow the supreme leader to be a lower-ranking cleric. As the Guardian Jurist (Vali-ye faqih), the supreme leader guides the country, protecting it from heresy and imperialist predations, and ensuring the laws of Islam are followed. The style "Supreme Leader" (Persian: رهبر معظم, romanized: rahbar-e mo'azzam) is commonly used as a sign of respect although the Constitution designates them simply as "Leader" (رهبر, rahbar). According to the constitution (Article 111), the Assembly of Experts is tasked with electing (following Ayatollah Khomeini), supervising, and dismissing the supreme leader. In practice, the Assembly has never been known to challenge or otherwise publicly oversee any of the supreme leader's decisions (all of its meetings and notes are strictly confidential). Members of the Assembly are elected by people in elections, and are approved by bodies (the Guardian Council) whose members are appointed by the supreme leader or appointed by an individual (Chief Justice of Iran) appointed by the supreme leader.

The Expediency Discernment Council of the System (Persian: مجمع تشخیص مصلحت نظام Majma'-e Tašxis-e Maslahat-e Nezâm) is an administrative assembly of Iran appointed by the Supreme Leader and was created upon the revision to the Constitution on 6 February 1988. It was originally set up to resolve differences or conflicts between the Majlis and the Guardian Council, but "its true power lies more in its advisory role to the Supreme Leader." According to Hooman Majd, the Leader "delegated some of his own authority to the council—granting it supervisory powers over all branches of the government" following President Mahmoud Ahmadinejad's election in 2005.

Members of the council are chosen by the Supreme Leader every five years.

The position of Commander-in-Chief (Persian: فرمانده کل قوا, romanized: Farmandehe Koll-e Qova), formerly known as Bozorg Arteshtārān (Persian: بزرگ ارتشتاران, lit. 'Great Army Leader'), is the ultimate authority of all the Islamic Republic of Iran Armed Forces, and the highest possible military position within the Islamic Republic of Iran. The position was established during the Persian Constitutional Revolution. According to the Constitution of Iran, the position is vested in the Supreme Leader of Iran and is held since 1981.

After the 1979 Iranian Revolution and 15 days after the inauguration of the first president Abolhassan Banisadr in February 1980, Ayatollah Ruhollah Khomeini delegated him as the Commander-in-Chief. According to Akbar Hashemi Rafsanjani, this was due to the illness of Ayatollah Khomeini and his concerns about the future of the revolution (in his absence). In the decree from Khomeini to Banisadr it is mentioned:

The Government of the Islamic Republic of Iran (Persian: نظام جمهوری اسلامی ایران, romanized: Nezâm-e Jomhuri-ye Eslâmi-ye Irân), known simply as Nezam (Persian: نظام, romanized: Nezâm, lit. 'the system'), is the national government of Iran.

Its constitution, adopted by a referendum, calls for separation of powers, with executive, legislative and judicial systems. The supreme leader of Iran is the country's head of state and commander-in-chief of the armed forces.

The Cabinet of Iran (Persian: هیئت‌دولت ایران, romanized: Heyatedovlat-e Iran) is a formal body composed of government officials, ministers, chosen and led by the President of Iran. Its composition must be approved by a vote of parliament. According to the Constitution of the Islamic Republic of Iran, a president may dismiss members of the cabinet, but must do so in writing, and new appointees must again be approved by parliament. Cabinet meetings are held weekly on Saturdays in Tehran and are chaired by the president. There may be additional meetings as circumstances require. The Supreme Leader of Iran Ali Khamenei has the power to dismiss cabinet members like ministers, vice presidents and presidents at any time, regardless of parliamentary decisions.