Few crimes in recent history have resounded around the world in the way that the assassination of Civil Rights Leader Dr Martin Luther King in 1968 did.
James Earl Ray was convicted of the killing. He already had a long list of convictions including for armed robbery when he was arrested in London's Heathrow airport.
Ray confessed to the murder, thus avoiding a trial and possible death sentence, but retracted his confession a few days later and spent time attempting to appeal claiming coercion and conspiracy. He asserted that a mysterious 'Raoul' was the real killer.
Ray was first assisted in his attempts by lawyer Jack Kershaw but eventually fired him. This was in part because of the fallout from an interview Kershaw arranged, complete with polygraph lie-detector, with Playboy.
Unhappy with the interview, not least that the lie-detector indicated he was lying, Ray accused Kershaw of taking a fee from the magazine and split from him.
The assassin died in 1998 whilst Kershaw lived on until 2010. Now his collection of James Earl Ray memorabilia is being offered at Case Antiques. This includes photographs of Ray and Kershaw working together, court documents, letters between the two and even a recording of the killer giving his version of the story.
The collection has been listed at $8,000-10,000 in the January 28 Tennessee auction, but we think it could easily sell for more than that despite, or perhaps because of, the macabre nature of such a holding.
Last year, the belongings of Ted Kaczynski, better known as the Unabomber, went under the hammer to contribute towards compensation for the families of his victims, and these fetched impressive prices.
The top lot was a set of handwritten journals by Kaczynski which brought an impressive $40,676. His 'hoodie' top and sunglasses (used as a disguise, sketched by the police and sometimes copied as a Halloween costume) brought $20,025.
Assassins in American history have also drawn interest. A wanted poster by John Wilkes Booth, the man who shot Abraham Lincoln, sold for $47,800 in 2011 at Heritage and several letters by the killer have sold for five-figure sums, going as high as $40,343.
In fact there are always people wanting to buy macabre items. In our stock we're currently offering the Pierrepoint collection - a large holding of materials connected to Great Britain's most prolific hangman, and we're sufficiently confident of its future value to be selling it with our 120% guarantee.