<P> A red herring is often used in legal studies and exam problems to mislead and distract students from reaching a correct conclusion about a legal issue, allegedly as a device that tests students' comprehension of underlying law and their ability to properly discern material factual circumstances . </P> <P> - William Cobbett, February 14, 1807, Cobbett's Political Register, Volume XI </P> <P> In a literal sense, there is no such fish as a "red herring"; it refers to a particularly strong kipper, a fish (typically a herring) that has been strongly cured in brine and / or heavily smoked . This process makes the fish particularly pungent smelling and, with strong enough brine, turns its flesh reddish . In its literal sense as a strongly cured kipper, the term can be dated to the mid-13th century, in the poem The Treatise by Walter of Bibbesworth: "He eteþ no ffyssh But heryng red ." </P> <P> Prior to 2008, the figurative sense of "red herring" was thought to originate from a supposed technique of training young scent hounds . There are variations of the story, but according to one version, the pungent red herring would be dragged along a trail until a puppy learned to follow the scent . Later, when the dog was being trained to follow the faint odour of a fox or a badger, the trainer would drag a red herring (whose strong scent confuses the animal) perpendicular to the animal's trail to confuse the dog . The dog eventually learned to follow the original scent rather than the stronger scent . A variation of this story is given, without mention of its use in training, in The Macmillan Book of Proverbs, Maxims, and Famous Phrases (1976), with the earliest use cited being from W.F. Butler's Life of Napier, published in 1849 . Brewer's Dictionary of Phrase and Fable (1981) gives the full phrase as "Drawing a red herring across the path", an idiom meaning "to divert attention from the main question by some side issue"; here, once again, a "dried, smoked and salted" herring when "drawn across a fox's path destroys the scent and sets the hounds at fault ." Another variation of the dog story is given by Robert Hendrickson (1994) who says escaping convicts used the pungent fish to throw off hounds in pursuit . </P>

Where does the phrase red herring come from