The power of words – slogans, graffiti, signs, newspaper stories – and the interpretive space opened up between their transmission and reception are explored in works such as Homage to the Walls of Athens 1941-19…, 1959, by Vlassis Caniaris (1928 - 2011), a palimpsest of sacking, wax and cloth saturated with whitewash plaster in which we see fragmentary hand-painted letters – including the letter E, for Eleftheria (freedom), for Ellás (Greece), for EAM, the National Liberation Front, the main movement of the Greek Resistance during the Axis occupation during World War II. Ian Hamilton Finlay’s La Rèvolution est un Bloc, 1992 – a wooden block carved with the words of the title and a central aperture reminiscent of a guillotine’s lunette – refers in content and form both to advances in secular democracy and social progress, and the bloodshed and unrest brought about by the French Revolution. Doug Aitken’s Free, 2016– a sculptural text work lined with shattered mirror – takes a single word and, through the actions of light and reflectivity, turns a ‘quick read’ into an endlessly shifting experience. Rirkrit Tiravanija's sculpture untitled 2013 (no no america), features a slogan used in chants and on banners by groups of Shia and Sunni military and civilians in Iraq over the past two decades.

How words are altered by context is a theme shared by Sarah Sze’s Calendar Series, 2013. When elements of the work were rejected by censors ahead of its inclusion in a biennial in China, rather than withdraw Sze created Calendar Series China Revision, 2015, applying strips of black acrylic paint to cover the content proscribed by the censors – all news references to China. For Protest, Sze represents the same New York Times covers, redacting all the written content except for references to China.

An example of his 'eraserhead' works, Christian Holstad’s She Was Fired for Questioning, 2011, introduces 24-carat gold leaf to the newspaper page, embellishing already jarring encounters between hard hitting news stories and advertisements for luxury goods while offering a commentary on ideas of class and status, politics and power that tends towards the surreal. Juxtaposing images of heated demonstrations with erotic or pornographic images, in the series Untitled (protest), 2012 – 2014, Richard Prince finds meaning itself is something to be stymied and subverted as a Dada-esque act of protest.

Borders, boundaries and thresholds are also a focus. Yayoi Kusama’s enveloping sculpture Prisoner’s Door, 1994, places the viewer in a space defined equally by forces of containment and release. The broken structure of Elmgreen & Dragset’s installation Prison Breaking / Powerless Structures, Fig. 333, 2002, imagines a moment of natural or manmade disaster, when the cell becomes physically powerless and the concept of captivity becomes meaningless. Flying above the gallery entrance, Chris Ofili’s Union Black, 2003, is inspired by David Hammons’ African-American Flag, 1990, based on the colours for the pan-African flag suggested by Marcus Garvey: red, black and green for African blood, skin and natural resources.

In Throw, 2016, by Wangechi Mutu, the eruptive gesture of demonstration merges with the (violent) placement of paint on a wall, referring to the languages of action painting and performance as well as to the act of throwing used in defiant protest.

Questions about what art that deals with newsworthy issues, or protests against the suffering of others should look like are asked by Isaac Julien who, in WESTERN UNION: Small Boats (The Leopard), 2007, brings together baroque pageantry and metaphor in a work that, referring to journeys made across the Mediterranean by Asians and Africans trying to enter Europe by sea, experiments with notions of cultural entanglement and the dissent between aesthetics and politics. In the series of works on paper Tell Me Your Thoughts on Police Brutality Miss ‘Spank Me Harder’, 2015, Kara Walker conflates different eras, idioms and attitudes to explore racism, its symbols and legacy from the American Civil War to very recent killings and assaults that have fuelled the Black Lives Matter campaign.

If how we make visible the plight of others and keep their stories debated and alive is one strand of the exhibition, tied up with this are ideas about how we defend and celebrate the freedoms we possess. Wolfgang Tillmans’ photograph NICE HERE: but ever been to KYRGYZSTAN? Free Gender-Expression WORLDWIDE, 2006, highlights the disparity between the growing freedoms enjoyed in progressive countries and worsening or non-existent rights in others. Jules de Balincourt’s painting Study for Idol Hands, 2015, depicts a throng holding aloft banners, each bearing a portrait of a different person – perhaps an “idol” as indicated by the title, though equally one thinks of the banners held aloft by relatives of the missing and disappeared in places such as Chile and Mexico.