We have reached a watershed moment in the life of the new South Africa.

The leadership of the African National Congress (ANC) must decide, soon, whether to persist with its campaign to force a suspect man into the presidency of this country regardless of the damage it is doing to its Constitution and its institutions, or whether it is going to turn to a more rational alternative in the national interest. The Constitutional Court judgments last week have brought us to this point. They mark the end of the road for Jacob Zuma’s drawn-out attempts to prevent potentially damning evidence being used against him in his pending corruption trial.

Only two throws of the legal dice remain for Zuma, and neither looks promising. One was the application that his lawyers made in the Pietermaritzburg High Court on Monday to have the charges declared unlawful because the National Prosecuting Authority (NPA) didn’t discuss them with him first. The other is an application to be made next month for a permanent stay of prosecution on the grounds that the case has taken too long to come to court and intense media attention means that Zuma can’t have a fair trial. I know of no legal precedent for either, so the prospects of success must be considered, well, dicey. Which has prompted speculation that the real purpose behind the applications is to start a new round of appeals and so delay the trial itself until after Zuma has been elected president — in the meantime using the ANC’s two-thirds majority in Parliament to pass a constitutional amendment preventing a sitting president from being prosecuted.

If so, last week’s Constitutional Court judgment may present some problems. In it Chief Justice Pius Langa laid down an injunction that “all courts should discourage litigation before trial … that seems to seek to delay the commencement of trials”. What, then, if Zuma finds that he has run out of legal options within the next few weeks? Will his supporters press on regardless, using brute political force and maybe even the threat of mob violence to override the rule of law and thrust him into the presidency — heedless of the damage this would do to the country and its economy and thus to the future of all our people? Or will they pause to consider the folly of that and start thinking rationally about what is in the best interest of our nation?

As I listen to the wild rhetoric about this being a political trial, about the Scorpions and the NPA and the judiciary, even the Constitutional Court, being part of a political conspiracy, I ask myself whether any of these people can have read either the indictment against Zuma or any of the judgments that have been delivered. Can they really believe that 31 of the country’s most senior judges are treasonous conspirators? I can’t believe that the sane people I know in the leadership of the ANC can really believe that. They have allowed their emotions to run away with them in the heat of this bitter power struggle, and it is time now to bring those emotions under control.

One look at the Zuma indictment is enough to show that this is no political trial. It is a criminal trial. What happened in this case is that when Schabir Shaik was convicted of corruption and sentenced to 15 years’ imprisonment in July 2005, he resigned as Zuma’s financial adviser and asked his lawyer to pack up all the documents relating to his financial dealings with Zuma and send them to Zuma’s lawyer, Michael Hulley. Two days after the boxes were delivered to Hulley, the Scorpions raided his office and seized them. They thereby gained possession of what must be one of the most massive paper trails in any commercial case investigation — with items seized in other raids, a total of 93 000 documents.

Working through this mass of material, the prosecution prepared a forensic report detailing all of Zuma’s financial records between 1995 and 2005. They itemised some 400 payments made to Zuma totalling more than R4 million. That report forms the basis of 16 charges against Zuma of racketeering, corruption, fraud and money laundering. None of the charges is political. All are criminal. And in fact only a small proportion involve the arms deal, with which he was initially charged. Essentially Zuma is accused of profiting from a racket that went on for 10 years and from which he continued to receive payments even after Shaik had gone to jail. In one respect only do Zuma’s supporters have a valid protest, and that is in contending that he is being selectively prosecuted. But that was not the fault of the Scorpions or the NPA: the case against him flowed out of disclosures in Shaik’s trial and it would have been a dereliction of duty if the investigators had not followed up on them. What is evident is that many people were involved in the arms deal, and the Sunday Times has now published material alleging that President Thabo Mbeki was a central figure and received a kickback of R30 million from a German company, of which he gave R28 million to the ANC and R2 million to Zuma.

This is not the first time that there have been allegations implicating Mbeki, and although he has denied them they are clearly the source of the bitterness that has poisoned the power struggle in the ANC — and is now beginning to endanger the whole country. There is only one way to end this struggle and save our democracy, and that is for Zuma and Mbeki to step down and make way for a new leader, perhaps Polokwane’s Plan B, Kgalema Motlanthe, to take over after an early election. A judicial commission of inquiry should also be appointed to investigate the whole catastrophic arms deal and grant amnesty to those who come forward.

It is true that neither Zuma nor Mbeki has been found guilty in a court of law, and in legal terms must therefore still be regarded as innocent. But both have been politically culpable for blocking attempts to have a thorough investigation by a judicial commission and the parliamentary Select Committee on Public Accounts into that disastrous deal, and of allowing it to fester uncleansed by public ventilation until it has poisoned our entire body politic. Mbeki in any event should take ultimate responsibility for the whole arms deal mess. In a democracy, the buck stops on the president’s desk. While Zuma’s image will remain tainted until he can clear it, either in court or before a commission of inquiry. It is incumbent on every political leader to place the interests of the country first.

Richard Nixon knew that when he stepped down after Watergate without being found guilty in a court. So now has Israel’s Ehud Olmert. He is accused of accepting a bribe from an American businessman, which he denies. He has not been found guilty in a court so must be presumed innocent, but he knows it is in the interests of his party and his country that he should go. So, too, is it now in the interests of the ANC and of the new South Africa that Zuma and Mbeki should go.

With acknowledgements to Allister Sparks and The Witness.