The decision ensures that Mr. Zuma won't have to answer allegations of criminal fraud and racketeering stemming from a controversial, multibillion-dollar arms deal dating to the 1990s. The case would have overshadowed the start of Zuma's presidency if, as expected, his governing African National Congress (ANC) party wins elections April 22 and selects him to lead the continent's most powerful country.
The head of the National Prosecuting Authority (NPA) said that his decision was based not on the quality of the government's case, which prosecutors think is strong, but on the emergence of wiretapped conversations from 2007 in which the then-head of special investigations discussed timing the case to increase the political damage to Zuma.
"I have come to the difficult conclusion that it is neither possible nor desirable for the NPA to continue with the prosecution of Mr. Zuma," said Mokotedi Mpshe, the head of the prosecuting authority.
In many ways, the decision creates even greater turmoil for a political system that many South Africans regard as increasingly rotten and a justice system that appears prone to bullying. South Africa is supposed to be a democratic model for the continent, but, two weeks before parliamentary elections that the ANC is projected to win comfortably, critics think that Mr. Mpshe was pressured by party insiders, some of whom have described past efforts to bring Zuma to court as counter to the ANC's long struggle to defeat white apartheid rule.
"We're almost in the worst of all worlds now," says Andrew Feinstein, a former ANC politician who resigned in 2001 to protest the party's refusal to investigate the arms deal thoroughly.
"The reality is they continue to have a strong case against Zuma. The prospect of some private prosecution [from opposition parties] is likely. So we continue to have this man tarnished by corruption, and that's not going to go away."
The charges, which Zuma has long denied, have dominated the election season in South Africa. Fired as deputy president in 2005 after the corruption charges surfaced, he maintained a strong following among the ANC's left wing, and wrested control of the party in 2007 after a bitter tussle with then-President Thabo Mbeki.
Zuma's supporters, who've described the case against him as politically motivated, cheered the decision. The Congress of South African Trade Unions issued a statement saying that it "feels vindicated and is obviously thrilled at the outcome."
The massive arms deal, in which the newly elected ANC government purchased some $5 billion worth of weapons, mostly from Europe, has cast a shadow over South African politics for more than a decade. In 2005, a close Zuma associate, Schabir Shaik, was convicted in the deal by a judge who described a "symbiosis" between the two.
Zuma was charged later that year, but the case was dropped after prosecutorial delays. In 2006, he was acquitted of rape after being accused by a woman he knew to be HIV-positive.
Prosecutors refiled corruption charges in December 2007, shortly after Zuma was elected the head of the ANC and became the odds-on favorite for president.
On Monday, Mpshe read aloud excerpts of wiretapped conversations in which Leonard McCarthy, then the head of the government's elite special investigations unit, and Bulelani Ngcuka, the former head of the prosecuting authority, discuss the timing of refiling the charges. In one recording, dated Dec. 24, 2007, after Zuma won the ANC presidency but before the charges were refiled, McCarthy is heard saying that he's a "Thabo man," an apparent reference to his support for Mr. Mbeki.
Mbeki has denied any involvement in the case against Zuma. Mr. McCarthy moved to the World Bank last September as the vice president of integrity and hasn't commented on the tapes.
Mpshe said that McCarthy's conversations constituted an "intolerable abuse" of the investigations process. However, critics say that if only the timing of the case was compromised – not the substance – it shouldn't have been dropped.
"At the moment it's not clear to us that the evidence of misconduct and inappropriate behavior warrants withdrawal of the charges," says Gary Pienaar, a senior researcher at the Institute for Democracy in South Africa, an independent policy institute. "We're asking whether there's an appropriate sense of proportion here."
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