Red herring is a figurative expression in which a clue or piece of information is or is intended to be misleading, or distracting from the actual question.[1] For example, in mystery fiction, where the identity of a criminal is being sought, an innocent party may be purposefully cast in a guilty light by the author through the employment of deceptive clues, false emphasis, "loaded" words or other descriptive tricks of the trade. The reader's suspicions are thus misdirected, allowing the true culprit to go (temporarily at least) undetected. A false protagonist is another example of a red herring.
In a literal sense, there is no such fish species as a "red herring"; rather it refers to a particularly strong kipper, meaning a fish—typically a herring but not always—that has been strongly cured in brine and/or heavily smoked. This process makes the fish particularly pungent smelling and, with a strong enough brine, turns its flesh reddish.[2] This term, in its literal sense as a strongly cured kipper, can be dated to the late Middle Ages, as quoted here c1400 Femina (Trin-C B.14.40) 27: "He eteþ no ffyssh But heryng red." Samuel Pepys used it in his diary entry of 28 February 1660 "Up in the morning, and had some red herrings to our breakfast, while my boot-heel was a-mending, by the same token the boy left the hole as big as it was before."[3]
The idiomatic sense of "red herring" has, until very recently,[2] been thought to originate from a supposed technique of training young scent hounds.[2] 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.[4] 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.[5] The dog would eventually learn to follow the original scent rather than the stronger scent. An alternate etymology points to escaping convicts who would use the pungent fish to throw off hounds in pursuit.[6]
In reality, the technique was probably never used to train hounds[7] or help desperate criminals. The idiom probably originates from an article published 14 February 1807 by radical journalist William Cobbett in his polemical Political Register.[2][8] In a critique of the English press, which had mistakenly reported Napoleon's defeat, Cobbett recounted that he had once used a red herring to deflect hounds in pursuit of a hare, adding "It was a mere transitory effect of the political red-herring; for, on the Saturday, the scent became as cold as a stone."[2] As British etymologist Michael Quinion says, "This story, and [Cobbett's] extended repetition of it in 1833, was enough to get the figurative sense of red herring into the minds of his readers, unfortunately also with the false idea that it came from some real practice of huntsmen."[2]