After a bitter campaign marred by a flood of disinformation spread via social media, Colombia will elect a new president on Sunday with the outcome seen as crucial for the future of the country's troubled peace process.
The right-wing senator Iván Duque, who leads his leftist opponent Gustavo Petro in all the polls heading into this weekend's run-off round, has vowed to revise key terms of the 2016 peace agreement with the Marxist Farc guerrilla group, now transformed into a political party called the Revolutionary Alternative Common Force.
In particular, he wants to toughen up penalties for former Farc commanders convicted of crimes committed during their half-century insurgency. The senator is a trenchant critic of the special justice system created by the 2016 peace accord. He says the terms ceded by outgoing president Juan Manuel Santos are too lenient for those facing charges of war crimes.
The Farc has said it will resist such efforts but its leader, Rodrigo Londoño, had to take to Twitter last week to deny reports that the movement would take up arms again if Mr Duque became president. An estimated 1,200 dissident Farc fighters have refused to demobilise and continue to engage the country’s military.
Ceasefire
Colombia's other guerrilla movement, the National Liberation Army, which is not party to the peace deal, has declared a ceasefire for Sunday's vote.
With various opinion polls giving him a double-digit lead, Mr Duque has rebuffed calls to debate his rival for office. A former guerrilla of the left-nationalist M-19 group, which demobilised in the late 1980s, Mr Petro has been the main target of a extensive misinformation campaign online. He has accused his opponent’s party of spreading various lies about him, including that he has an illegitimate daughter whom he refuses to acknowledge.
He has also faced efforts to smear him as a threat to Colombian democracy who would seek to copy the failed chavista model that has ruined neighbouring Venezuela.
Bidding to ally such fears when receiving the endorsement of the country’s Green Alliance, the former mayor of Bogotá last week produced 12 commitments on marble tablets that he said he would keep displayed on his desk if elected. These included a promise of no expropriations and to support the private sector, to respect the peace agreement with the Farc and not to call a constitutional assembly.
This last pledge meant abandoning his previous proposal to rewrite Colombia’s constitution, sparking fears he is a closet autocrat given such a tactic has been used by presidents across the region seeking to entrench themselves in office.
Human rights abuses
During the campaign Mr Petro has sought to highlight the close links between his opponent and former president Álvaro Uribe, who is facing multiple charges of human rights abuses and corruption.
Mr Duque is a protege of the former president who remains a hero for many on the right for his aggressive military campaign against the Farc after becoming president in 2002. It was Mr Uribe who led the campaign that voted down the peace deal in a referendum, forcing Mr Santos to push it through the congress instead, thus stripping it of legitimacy in the eyes of many Colombians.
Mr Uribe remains the most divisive figure in Colombia's deeply polarised society. He was the most voted for senator in congressional elections in March despite public prosecutors saying they have uncovered evidence of widespread abuses committed by his circle. His brother Santiago is on trial accused of running a right-wing paramilitary death squad known as the 12 Apostles out of a family ranch near the city of Medellín.
Acrid campaign
Mr Uribe has denied that, if elected, his protege will interfere with the justice system in order to benefit him.
The acrid campaign, especially the online offensive against Mr Petro, has highlighted the growing unease within much of the Colombian elite at the emergence of a democratic progressive left challenge to its previously automatic control of the presidency.
Sunday’s vote will be the third time in the last four contests that a candidate from the left of the political spectrum has forced the contest to a run-off round, even if each time previously they fell far short of ultimate victory.