Gareth Peirce, a campaigning lawyer who has been investigating the case on behalf of Giuseppe, has a breakthrough when she tries to access Giuseppe's file and is able to look instead at Gerry's. She finds vital police documents in the file that are marked "Not to be shown to the Defence". During the course of their appeal, the production of these documents leads to a triumphant scene in court when Peirce produces the evidence that the police have been lying throughout about the existence of a witness who had provided Conlon with an alibi during their initial investigation. This leads to the overturning of the verdict and immediate release of the Guildford Four.