Channel 4 is facing questions over TV show The Greatest Auction after emails revealed a dealer warned producers that art tentatively attributed to Banksy and sold for £250,000 was being billed as not genuine by a company involved in its restoration.
Jeff Salmon, an art collector who has appeared on a number of Channel 4 shows, was told he was not required at the filming of the relevant auction scenes on the primetime show after he pointed programme producers to the testimony of a firm that had managed the piece.
