The depiction of Russia as a mysterious country of riddles and enigmas by former British Prime Minister Winston Churchill serves as an apt description of the political imbroglio over Deputy President Jacob Zuma and his quest to succeed Thabo Mbeki as president.

The trial for corruption, fraud and theft of Durban businessman Schabir Shaik is nearly as much about Zuma as it is about Shaik, as well as the third main player in the drama: the French-based international armaments company Thomson-CSF in which Shaik had an interest.

But Zuma, who as deputy president is already only a few heartbeats away from the presidential office, is not in the dock with Shaik, who was, and still is, his financial advisor.

The charge sheet in the long-awaited trial - which began yesterday - links Shaik and Zuma inextricably in a labyrinthine saga of allegedly corrupt financial manoeuvres, the purpose of which was to win the support of Zuma for Shaik in his pursuit of lucrative government contracts, particularly in relation to the multi-billion rand arms deal.

The indictment typecasts Shaik as the briber and Zuma as the recipient of the bribe, or bribee. It is thus understandable that the absence of Zuma in the dock has led to characterisation of the courtroom drama as Hamlet without the Prince of Denmark.

The explanation for the absence of Zuma goes back to August last year, when the then National Director of Prosecutions, Bulelani Ngcuka, made a startling two-fold announcement: firstly, that there was a prima facie case of corruption against Zuma, and, secondly, that it had nevertheless been decided not to prosecute him as there was no guarantee of securing a conviction.

The Concise Dictionary of Law defines a prima facie case as one that is supported by sufficient evidence for it to be taken as proved in the absence of convincing evidence to the contrary.

That implies that Ngcuka was under a legal obligation to charge Zuma in order to ascertain the truth and, as important, to give Zuma an opportunity to rebut the charges.

A conundrum that requires explanation thus lies at the heart of the Ngcuka's decision not to prosecute Zuma if he believed he had a prima facie case against him.

One explanation is that Ngcuka, misunderstanding the phrase, pronounced the state had a prima facie case when it had not compiled sufficient evidence to establish a presumption of guilt requiring comprehensive rebuttal.

Given Ngcuka's legal training that is unlikely.

An alternative explanation is that Ngcuka had a genuine prima facie case but succumbed to political pressure not to press charges against Zuma, preferring to take a more circuitous route by charging Zuma's financial adviser Schabir Shaik and thereby, to use a military analogy, to opt for indirect attack instead a frontal assault.

It should be recalled that by August 2003 Zuma had already begun to react defensively against the national prosecuting authority and the directorate of special operations, aka the Scorpions.

His defence took two forms: a visible one, manifest by public statements accusing the Scorpions of maliciously leaking information to the media to embarrass him, and an invisible one, evidenced by his reported connivance in an attack on Ngcuka's political integrity by making it known to a select journalist that Ngcuka had been investigated by the ANC in the late 1980s as a suspected double agent for the then white-dominated government. On the second point it should be remembered that former ANC intelligence operative Mo Shaik admitted during the Hefer Commission of Inquiry late last year that he had leaked the information about Ngcuka and that he was a "flag-bearer" for Zuma.

It is significant, too, that there was strong support for Zuma within the ANC-led tripartite alliance during 2003.

One thinks of the the investigation into Zuma's financial affairs that could be likened to a Hollywood-style film script by ANC Secretary-General Kgalema Motlanthe and the singing of pro-Zuma songs at the Congress of SA Trade Unions conference.

Since then further evidence of support for Zuma has surfaced. Apart from the government statement that it accepted his word and adamant ANC Youth League declarations in his favour, a Markinor survey shows that nearly a third of South Africans, and close to half of the ANC's supporters, think Zuma is the victim of a conspiracy to discredit him.

Zuma's strong and growing popularity calls into question the widely held assumption that a guilty verdict in the Shaik trial will necessarily eliminate him as a presidential candidate. As long as Zuma retains a significant measure of backing, it may neutralise the adverse implications of a conviction in the Shaik trial.

To recognise that reality is not to welcome it. For a politician to occupy the highest political office while there is even a vestige of suspicion that he or she was party to corruption cannot be a salutary development for SA's fledgling democracy.

Even if Shaik is acquitted, questions will remain about Zuma's competence to govern a society as complex as South Africa.

It is not a commendation that he could not balance his household budget, as shown by his admission to parliament of having had to borrow money from individuals, including two high profile businessmen seeking contracts from government, Shaik and Vivien Reddy.

His decision to accept loans from them raises questions about his political judgment, even if they were loans on which he had to pay interest as he averred in his statements to parliament last year.

The loans exposed him to potential pressure from ambitious moguls and a conflict of interest between his duty as deputy president and his aspirations as a private citizen.

It has to be asked why he did not borrow money from banks if cash-flow problems made it difficult to fulfil his responsibilities as a father and husband.

Zuma's political strength may be partly the product of the absence of credible alternative candidates, perhaps because potential rivals do not judge it opportune to declare themselves in the present charged atmosphere.

That could change before the ANC 2007 national conference, when a successor to Mbeki will be elected as ANC leader, particularly if as yet unknown details of the Shaik-Zuma nexus emerge during the anticipated courtroom interrogation of more than 100 scheduled witnesses.

The Star's contributing editor Patrick Laurence is the editor of Focus, journal of the Helen Suzman Foundation

With acknowledgements to Patrick Laurence and The Star.