Among the legal texts in Brendan Grehan’s office is an image of the 1874 painting by Claude Monet ‘Argenteuil Basin with a single boat’. Far from being an appreciation of Monet’s impressionist masterpiece, the picture, a gift from a colleague, shows a massive rip through the artwork where it was punched by Andrew Shannon in the National Gallery in 2012. Despite eyewitnesses to the event, Grehan, representing Shannon, managed to deadlock the jury with his client’s ‘unusual’ defence that he felt faint and collapsed into the €10 million painting due to a heart condition. The senior counsel even quoted the…