Nairobi - Kenya's Supreme Court judges completed on Tuesday their hearing of an opposition challenge to the August 8 poll and said a ruling will be delivered on Friday.Opposition leader Raila Odinga argued the presidential poll was rigged and took his case to the court, challenging the election commission's declaration of President Uhuru Kenyatta's re-election with 54% of the vote. After hearing closing arguments from lawyers representing the National Super Alliance (NASA) opposition coalition, the Independent Electoral and Boundaries Commission (IEBC) and Kenyatta, Chief Justice David Maraga said, "That brings us to the end of the hearing. We will deliver judgement on Friday."Odinga alleges that hacking and fraud delivered victory to Kenyatta and believes it is the third time in a row that he has been cheated of a rightful win.The disputed election in 2007 led to politically-motivated ethnic violence in which over 1 100 people died. In 2013 Odinga took his dispute to the courts, and lost.'A clerical error'On Tuesday the court was handed reports from its own registrar and a panel of court appointed experts assessing allegations of errors and malpractice that the opposition say mean the election result should be annulled and the poll re-run.In his final submission James Orengo, a NASA official and lawyer, said the reports told "a very, very sad story" of irregularities, pointing to a number of unsigned tally forms and others lacking security features, that he said could affect as many as five million votes.Orengo described the pair of reports as "two smoking guns" and called on the Supreme Court to declare Kenyatta's election invalid.However, lawyers for the IEBC and Kenyatta told the court the reports in fact validated their argument that the vote was free and fair."All they have been talking about is this technicality or that technicality," said IEBC lawyer Paul Muite of the NASA case. "The results announced captured and represented the will of the Kenyan people."Fred Ngatia, acting for Kenyatta, said that discrepancies were nothing more than "a clerical error"."This was a fair election in which the integrity of the vote was protected as far as is humanly possible," he said.The seven Supreme Court judges will now consider the evidence and deliberate before giving their ruling on Friday after which Kenyatta will either be sworn in or the election re-run.