In one of his Rumpole of the Bailey episodes, John Mortimer QC put the following words into the mouth of a litigant in a case concerning works of art and specifically paintings: “I have confounded the connoisseurs!” Expert opinion about the authenticity of pictures is notoriously fraught with difficulty and division. Although the particular issue was not authenticity as such, Australia saw a celebrated instance of the problems surrounding opinions about the forms and merits of artworks in the litigation brought in 1944 by other competitors against the award of the Archibald Prize to Sir William Dobell for his portrait…