The ANC is alleged to have used the services of a group called the Media Advisory Team to attract voters through the use of social media, chat shows and a news website.
But the team is also alleged to have produced and planted fake information about its political opponents.
The accusation came to light when one of the people involved, Sihle Bolani, filed a case in court suing the ANC for 2.2 million rands (150,000 euros), claiming the party owes her the money for work she did.
Sihle Bolani also recorded on her cellphone some of the group's "war room" meetings with ANC's general manager Ignatius Jacobs. Recordings she shared with the amaBhungane Centre for Investigative Journalism and which were made public on Sunday via the City Press newspaper.
The Democratic Alliance opposition party has said it is going to raise the matter with the Independent Electoral Commission in a meeting on Tuesday 31 January and ask for a full investigation into any violations of the Electoral Code of Conduct.
"The ANC's decision to run a black ops smear campaign against the Democratic Alliance and other political opponents undermines the function of free and fair elections," said Mabine Seabe, the spokesperson of the DA's leader, Mmusi Maimane. "And this is also condemned through our Electoral Act which states that a party cannot disseminate or produce information that is untrue or tarnish the name of any other political opponent”
He explains that a violation of this code of conduct carries a fine of up to 20,000 rands and, in the most extreme cases, the deregistration of the political party. The DA's legal team is examining whether to lay criminal or civil charges against the ANC.
One product of this alleged disinformation campaign are fake election posters of Julius Malema, the leader of the Economic Freedom Fighters, holding an AK-47 with "Take up arms and fight" written at the top.
The EFF believes the smear campaign was carried out with the full cooperation of the ANC.
“We also believe that no amount of propaganda will ever restore the reputation of thieves and murderers, that’s why they still lost Johannesburg and Tshwane,” EFF spokesperson Mbuyiseni Ndlozi said.
The ANC denies being involved in the whole operation.
“The ANC categorically rejects with the contempt that they deserve the report that we would have funded some covert operations called the black ops campaign targeting opposition parties” said Khusela Sangoni, ANC’s communications manager, “We are obviously concerned that an employee of the ANC's general manager has been implicated and in this regard the ANC is instituting an internal investigation to get to the bottom of these allegations.”
As head of the department of information and publicity and responsible for communication, Sangoni is adamant that the ANC never contracted the services of the Sihle Bolani or anyone else mentioned as part of this campaign.
William Bird, the director of Media Monitoring Africa, believes that most of the allegations contained in the legal documents are true.
"Nothing that the ANC or those involved are saying does really anything to disprove that.” he says.
“Did some members within the ANC sanction this? Yes that certainly seems to be the case, if you look at Jacobs. But I don't think that any senior executive of the ANC would be that unbelievably stupid to make those kind of decisions.”
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