Fallen leaders

Lula has been found guilty of corruption and money laundering for his involvement in the "Car Wash" scandal, an extensive corruption probe that uncovered widespread bribery among Brazil's elites. Lula, who held the presidential office between 2003 and 2010, was sentenced to 12 years in jail. He still has a chance to appeal the ruling.

Cristina Fernandez, who served as Argentina's first lady and then as its president from 2007 to 2015, was indicted on corruption charges in 2016. She was accused of granting public construction contracts to favored companies. She denies any wrongdoing. Fernandez is now seeking a political comeback, which some observers say is a bid to seek immunity against the charges.

Following months of public outcry over a wave of corruption allegations, South Korea's first female president Park Geun-hye was removed from office. She has been charged with extortion, bribery and abuse of power. Park was impeached in December 2016.

The 71-year-old Olmert, who was premier between 2006 and 2009, was convicted of corruption in 2014. He entered prison in February 2016 but was was released in early July 2017 after his sentence was shortened. He was the first former prime minister of Israel to go to prison. Benjamin Netanyahu was his successor.

Adrian Nastase was convicted of corruption charges in 2012 and sentenced to a two-year imprisonment term. At the time when the sentence was pronounced, he was the only head of government sentenced to prison in the 23 years following the Romanian Revolution. He was Romania's prime minister from 2004-2006.

Charles G. Taylor was sentenced to 50 years in prison in 2012 for his role in atrocities committed in Sierra Leone during its civil war in the 1990s. Taylor was the first former head of state convicted by an international tribunal since the Nuremberg trials in Germany after World War II. He was Liberia's president from 1997-2003.