An assassination market is a prediction market where any party can place a bet (using anonymous electronic money and pseudonymous remailers) on the date of death of a given individual, and collect a payoff if they "guess" the date accurately. This would incentivise assassination of individuals because the assassin, knowing when the action would take place, could profit by making an accurate bet on the time of the subject's death. Because the payoff is for accurately picking the date rather than performing the action of the assassin, it is substantially more difficult to assign criminal liability for the assassination.
Early uses of the terms "assassination market" and "market for assassinations" can be found (in both positive and negative lights) in 1994's "The Cyphernomicon" by Timothy C. May, a cypherpunk. The concept and its potential effects are also referred to as assassination politics, a term popularized by Jim Bell in his 1995-96 essay of the same name.
In part ten of his essay, Bell posits a market that is largely non-anonymous. He contrasts this version with the one previously described. Carl Johnson's attempt to popularise the concept of assassination politics appeared to rely on the earlier version. There followed an attempt to popularise the second in 2001 that is ongoing today.
Technologies like Tor and Bitcoin have enabled online assassination markets as described in parts one to nine of Assassination Politics.
The first prediction market entitled 'Assassination Market' was created by a self-described crypto-anarchist in 2013. Utilising Tor to hide the site's location and Bitcoin based bounties and prediction technology, the site lists bounties on politician Barack Obama, economist Ben Bernanke and former justice minister of sweden Beatrice Ask.