How does Iran's theocratic system of power work?

Iran's Supreme Leader Ayatollah Ali Khamenei was reported killed in strikes on Saturday by the U.S. and Israel, which, if confirmed, could throw into jeopardy continued clerical rule in the Islamic Republic.

The complexities of Iran's ruling system, the ideological nature of its support base, and the power of its Revolutionary Guards make it hard to predict what might come next.

The following explains how the system was meant to operate, how a new supreme leader could be chosen, and how the attack ⁠on Iran may have changed the equation:

WHO COULD SUCCEED KHAMENEI AS 'SUPREME LEADER'?

The ⁠supreme leader must be a cleric under Iran's system of vilayat-e faqih: guardianship of the Islamic jurist. The theory holds that until the return of the Shi'ite Muslim 12th Imam, who disappeared in the ninth century, power on earth should be wielded by a venerable cleric.

Under Khamenei and his predecessor, the founder of the Islamic Republic Ayatollah Ruhollah Khomeini, the supreme leader has the last say in ⁠all matters of state, but the system has never faced such a challenge before.

Khamenei's sway has often been wielded through close advisers. But in the aftermath of Saturday's strikes it is far from clear how many of those top figures have survived.

Khamenei, 86, was never publicly recorded as having named a successor and it's not clear who might replace him if he is confirmed as dead.

His son, Mojtaba Khamenei, has at times been seen as a possible candidate but his fate is also unclear. His predecessor's grandson, Hassan Khomeini, has been another, as have some older senior clerics.

No remaining figure enjoys Khamenei's standing or clout, and any successor might struggle to dominate powerful interest groups such as the Revolutionary Guards or top clerical councils.

WILL IRAN'S THEOCRACY PERSIST?

Iran's clerical elite control powerful bodies that extend their influence throughout the political system.

The Assembly of Experts, made up of senior ayatollahs elected every eight years, is the body that appoints the supreme leader. The constitution also gives it power to question and even dismiss a leader, but it has never done so.

In practice the choice would likely be made by the ⁠most senior ⁠figures in the Islamic Republic and then approved by the assembly. But with some top Revolutionary Guards leaders confirmed as dead, it is far from clear who would sway the decision.

The Guardian Council - half appointed by the leader and half by the judiciary chief - can veto laws passed by parliament and disqualify election candidates, a mandate that has been used to block potential critics of Khamenei.

Iran follows Shi'ite interpretations of Islamic sharia law and its judges are also clerics under a judiciary chief named by Khamenei. The current head, Gholamhossein Mohseni Ejei, was sanctioned by Western countries for a violent crackdown on protesters in 2009 when he was intelligence minister.

Other influential clerics include former judiciary chief Sadiq Larijani, the brother of Khamenei adviser Ali Larijani; Assembly of Experts member Mohsen Araki; and Tehran Friday prayer leader Ahmad Khatami.

WHAT ROLE COULD THE REVOLUTIONARY GUARDS PLAY?

Unlike the ordinary military, which comes under the Defence Ministry in the ⁠elected government, the Islamic Revolutionary Guards Corps answers directly to the supreme leader.

Its commander Mohammed Pakpour was killed on Saturday, three sources familiar with the matter said.

Formed soon after the revolution, the IRGC's role defending the Islamic system greatly expanded during the 1980-88 war with Iraq and it is now the strongest and best-equipped section of Iran's armed forces.

Over the decades, the Guards have extended their influence through the worlds of politics and business, gaining in power at home and abroad.

The Quds Force, an elite Guards unit, has spearheaded Iran's regional strategy of supporting affiliated Shi'ite groups across the Middle East, most notably in Lebanon and Iraq. That strategy was hard-hit by the U.S. assassination of Quds Force commander Qassem Soleimani in a 2020 air strike in Iraq, and by Israel's pummelling of Lebanon's Hezbollah in a 2024 war.

The Basij ⁠militia, a part-time ‌paramilitary force under Guards ‌control, is often used to quell protests inside Iran.

Since the early 2000s, the Guards' economic power has ⁠grown as its contracting company Khatam al-Anbiya won projects worth billions of dollars in Iran's oil and ‌gas sector.

The targeted nature of Israeli strikes on senior Guards commanders has raised questions over possible Western intelligence penetration in the corps' upper echelons.

Still, the corps will likely play a major role in what happens to the Islamic Republic next.

WHY DOES IRAN ⁠ALSO HAVE ELECTIONS?

Iranians elect a president and a parliament to four-year terms. The president appoints a government that handles ⁠daily policy within parameters permitted by the supreme leader.

During the early years of the Islamic Republic the votes drew mass participation. But Guardian Council restrictions on candidates, ⁠a much-disputed election outcome in 2009 and the supremacy of unelected parts of the stateundermined faith in electoral politics.

President Masoud Pezeshkian, seen as a moderate, was elected in 2024, defeating a noted hardliner. Israel said he too had been targeted in Saturday's strikes and there was no confirmation later in the day of his status.