The same state advocate who successfully prosecuted fraudster Schabir Shaik will lead the corruption case against former president Jacob Zuma. News24 has reliably learnt that Advocate Billy Downer SC, a deputy director of public prosecutions in the Western Cape, will lead the State's case against Zuma, which is scheduled to start in the Durban High Court on Friday morning.Downer is a veteran prosecutor who recently successfully convicted former Western Cape top cop Arno Lamoer.READ: Edward Zuma: 'There's a witch-hunt against my father'He led the National Prosecuting Authority's (NPA) investigation into the arms deal since the early 2000s and prosecuted Shaik, Zuma's former financial adviser, between 2004 and 2006.Downer was also leading the Zuma prosecution in 2009 when former acting prosecutions boss Mokotedi Mpshe dropped charges against the former president.Advocate Moipone Noko, director of public prosecutions in KwaZulu-Natal, will still oversee the case, but Downer will lead the State in court. Judge Themba Sishi to presideMeanwhile, the judiciary has refused to name the judge who will be presiding over the matter. "Unfortunately we can't disclose that until the date of the hearing," spokesperson Nathi Mncube told News24.However, News24 understands that Zuma will appear before Judge Themba Sishi.Zuma is facing one count of racketeering, two counts of corruption, one count of money laundering and 12 counts of fraud.ALSO READ: State lines up 207 witnesses for Zuma trialOn April 6, 2009, then NPA head Mokotedi Mpshe said recordings of telephone conversations between then Scorpions boss Leonard McCarthy and former NPA boss Bulelani Ngcuka showed political interference in the decision to charge Zuma. The two were recorded discussing the timing of bringing charges against Zuma. The charges related to his alleged involvement in the country's multibillion-rand arms deal.'Reasonable prospects of successful prosecution'According to the NPA, the conversations provided evidence at the time of collusion against Zuma, between former NPA officials and former president Thabo Mbeki. The charges were subsequently withdrawn just before Zuma was sworn in for his first term as president. However, in 2016 the North Gauteng High Court in Pretoria found that there was no reason for the NPA not to proceed with the prosecution.Zuma and the NPA appealed this decision in the Supreme Court of Appeal. The court dismissed the appeal in October last year. This after Zuma and the NPA made an about-turn and said the decision not to prosecute him was irrational.NPA boss Shaun Abrahams had to review the original charges and decide whether to go ahead with the case or not.On March 16, Abrahams announced that the NPA had decided to go ahead with the prosecution because it believes there are reasonable prospects of a successful prosecution.