Mehdi Karroubi is an influential Iran

Iran

Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...

ian reformist politician

Politician

A politician, political leader, or political figure is an individual who is involved in influencing public policy and decision making...

, democracy activist, mojtahed, and chairman of the National Trust Party

National Trust Party (Iran)

National Trust Party , also translated as National Confidence Party, is an Iranian political party based on reformist and populist message. NTP was established in 2005 by former Parliament speaker Mehdi Karroubi following his controversial defeat in 2005 presidential election...

. He was Chairman of the parliament

Majlis of Iran

The National Consultative Assembly of Iran , also called The Iranian Parliament or People's House, is the national legislative body of Iran...

 from 1989 to 1992 and 2000 to 2004, and a presidential candidate in the 2005

Iranian presidential election, 2005

Iran's ninth presidential election took place in two rounds, the first on June 17, 2005, the run-off on June 24. Mohammad Khatami, the previous President of Iran, stepped down on August 2, 2005, after serving his maximum two consecutive four-year terms according to the Islamic Republic's constitution...

 and 2009 presidential elections

Iranian presidential election, 2009

Iran's tenth presidential election was held on 12 June 2009, with incumbent Mahmoud Ahmadinejad running against three challengers. The next morning the Islamic Republic News Agency, Iran's official news agency, announced that with two-thirds of the votes counted, Ahmadinejad had won the election...

.

He is a founding member and former chairman of the Association of Combatant Clerics party. Karroubi is a critic of the Guardian Council

Guardian Council

The Guardian Council of the Constitution , also known as the Guardian Council or Council of Guardians, is an appointed and constitutionally-mandated 12-member council that wields considerable power and influence in the Islamic Republic of Iran....

 and Iran's Judicial System. By appointment of the Supreme Leader

Supreme leader

A supreme leader typically refers to a figure in the highest leadership position of an entity, group, organization, or state, who exercises strong or all-powerful authority over it. In religion, the supreme leader or supreme leaders is God or Gods...

, he was a member of the Expediency Discernment Council

Expediency Discernment Council

The Expediency Discernment Council of the System is an administrative assembly appointed by the Supreme Leader and was created upon the revision to the Constitution of the Islamic Republic of Iran on 6 February 1988...

 and an adviser, posts he held until resigning from all his posts on June 19, 2005 after the first round of the 2005 presidential election.

He has been described as a "moderate" with a "mostly rural" base of support.
Karroubi considers himself a pragmatic reformist and now is one of the leaders of the opposition movement in Iran.
Mehdi Karroubi is from a Shia clerical family in Aligoudarz, a city in the western part of Lorestan province

Lorestan Province

Lorestan Province is a historic territory and province of western Iran, amidst the Zagros Mountains. The population of Lorestan was estimated at 1,716,527 people in 2006.Lorestan covers an area of 28,392 km²...

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