Occasionally an image will so trouble the people looking at it – so appal them with its curdled familiarity, its stolen innocence, its senselessness – that it will bring with it Rankine’s “new kind of logic”. Irrespective of what happens in court, the last picture of Cassius Turvey should do this. No country should be able to look at his unmoving face and not call into question all the structures and prejudices and privileges that went into his death.