In 1981, South African artist Sue Williamson went to Cape Town’s District Six, where black and mixed-race families’ houses had been torn down as part of the apartheid government’s efforts to entrench segregation in cities. She collected rubble from these forced removals, then assembled it in the pristine white of an exhibition space not far away for one of her earliest gallery installations, “The Last Supper”.

“It generated a lot of publicity at the time,” says Williamson, 80, speaking in her Cape Town studio and recalling how some security police visited the show: “I was pleased they came.” In a 2015 interview, she said of the work: “As people interested in art, you have come to look at the installation of rubble. But actually, you’re passing it on a much larger scale every single day of your lives as you drive in and out of Cape Town.”

This impulse to use the textures, forms and even the physical artefacts of destruction and protest infuses Williamson’s whole body of work, and now important pieces in her long career as an artist and activist — poised somewhere between heated truth-telling and cooler, more conceptual ploys — are due to go on show at Goodman Gallery in London in March.

One work on display brings some of the rubble of District Six to London: hairpins, sweet wrappers, crockery shards, other bits and pieces, all preserved in casting resin. A companion piece documents the interior of a house belonging to Naz Gool Ebrahim, a community leader and friend of the artist. On the eve of its destruction, Ebrahim invited friends and family to graffiti the walls in a gesture of defiance and memory: “Welcome to the Last Supper” was what Ebrahim wrote.

Williamson, whose family emigrated to South Africa from the UK in 1948, began her artistic career with screenprints of South African women who were influential in the liberation struggle: they became iconic and much-loved portraits that circulated as postcards in the 1980s. Having worked abroad as a copywriter in Mad Men-era New York, she returned to South Africa and was “jolted out of lethargy” by the events of 1976, when the youth of Soweto rose up against the apartheid state.

That year, she says, marked “a jagged faultline” in the country’s history. It signalled the beginning of the end of white-minority rule: a rolling wave of strikes, boycotts, stay-aways, rallies and mass movements that reached a crescendo of hope and anger in the 1980s.

Williamson documented the paintings, drawings and sculptures of this moment — along with its posters, linocuts, comics, banners, T-shirts and graffiti — in her influential 1989 book Resistance Art in South Africa. “I rushed in where angels fear to tread,” she says of her work as critic, “because I’d never done art history or anything.” In the introduction, she quotes some lines from the writer Menán du Plessis which serve as a good description of Williamson’s own practice: “It is not the morally self-conscious art of liberal protest, nor is it the defiant art of outrage, it is the diverse, complex, extraordinarily rich art of resistance. It is rooted directly in the context of struggle.”

After Nelson Mandela’s African National Congress party was voted into power in 1994, Williamson turned her attention to the hearings of the Truth and Reconciliation Commission (TRC) from 1996 to 1998. The TRC was tasked with hearing from victims and perpetrators of human rights abuses and could grant amnesty for politically motivated killings, on the basis of full disclosure.

Here, says Williamson, was the zero-sum game built into the project: “It was only the guarantee of amnesty which made security operatives and political assassins emerge from the shadows and reveal what had happened to missing loved ones. But this often came at the expense of justice, accountability or prosecution.” Once globally celebrated and emulated, the TRC is now viewed with misgivings by many younger South Africans.

Williamson’s series “Truth Games” (her most visually distinctive work, to my eyes) takes us into these shifting, murky zones. Its panels are, quite literally, a sliding puzzle. The background layer is blown-up newsprint photographs of TRC hearings: victim on the left, perpetrator on the right, event in the middle — but cropped or magnified in a way that often renders the central trauma cryptic or confusing. Over the images are moveable, semi-transparent slats: bits of text from TRC testimony or news reports. To fully engage with the work, you need to move the words around, a process that reveals some archival details while obscuring others.

Williamson worked briefly as a journalist early in her career, when being a woman in a Durban newsroom meant that she was seldom permitted to cover important stories. Instead, her job was to compile scrapbooks of news clippings — “guard books” — and this archival impulse has never left her. Boxes of cut and pasted fragments underlie what she calls the “skeletal dialogue” of her TRC works. “I was interested in the exact words people used to present their case,” she says. “I wanted to give the most convincing language from each side.”

The words slide over the dots of old newsprint pictures: nervous tics, grimaces, involuntary smiles, narrowed eyes. Even in the low-quality photographs, she remarks, “the body language of the speakers came through”.

Many of Williamson’s early works grew out of personal relationships forged in collective struggle. But as her art moved into the public domain (and further into the post-apartheid era), it was subject to critiques around the ethics of her representing others’ lives across divides of race, class and culture. But Williamson, in the untroubled but careful way that she talks about her work, seems unfazed by this. She says: “You need to be very careful when doing this kind of work. But people know that if they start a project with me, there’s no commitment to finish. They can pull out at any time, if they feel uncomfortable.”

On one screen of this two-channel installation is a young woman, Candice Mama. She tells the story of encountering Eugene de Kock, commander of apartheid’s most notorious death squads and the man who killed her father. “It’s a pleasure to meet you” is what De Kock says to her and each family member when they meet him in prison, while a pastor presides. Mama speaks of being convinced by De Kock’s sincerity and remorse. A photograph flashes up of the family with apartheid’s chief killer, in a maximum-security jumpsuit. “Do you forgive yourself?” Mama asks De Kock. He replies that nobody who has done the things he has done can forgive themselves.

On the other screen is a young man, Siyah Ndawela Mgoduka, listening. He also lost his father, but his only contact with the killers is a memory of being given the middle finger across a TRC hearing by a security policeman. Mgoduka cannot quite bring himself to believe in the story Mama is relating so sincerely right next to him, even as he might want to. It is a story that has the sound of having been told many times before, of having become (as many TRC cases did) an exemplary tale, a parable.

Mama and Mgoduka’s body language when listening to each other, the complex expressions that pass over their faces — these unspoken elements say so much. The digital split screen (used in many of Williamson’s more recent works) shows how her art has stayed responsive to changing times and technologies across four decades. Here and elsewhere, the work presents us with the puzzle of two deeply felt, equally valid truths: truths that each listener wants to respect but also finds uncomfortable, unworkable, unresolved.

Artworks courtesy of Sue Williamson and Goodman Gallery London, Johannesburg, Cape Town

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