Criminologists have a name for a person who hires a hit man: instigator. They also confirm what news stories suggest: Lots of instigators get caught because they don’t know what they’re doing. After all, most of us don’t socialize with professional killers. The average person therefore looks to acquaintances or neighbors for referrals, or finds his way to criminal bottom-feeders who are likely to be inept and inexperienced. The former may be inclined to call law enforcement, while the latter may lose their nerve or botch the job. Which helps explain why so many murders for hire don’t produce any dead bodies.

In 2003, the Australian Institute of Criminology published an analysis of 163 contract-killing cases (some completed, others merely attempted) in Australia; it remains one of the most significant studies ever conducted of the subject. The authors determined that 2 percent of all murders in Australia were contract killings and that contracts were, in some cases, surprisingly affordable. One unfulfilled contract was for 500 Australian dollars; another job was completed for just $2,000. Among other key findings, nearly 20 percent of all contracts involved a romantic relationship gone wrong, and 16 percent were financially motivated.

Another study, this one of contract killings in Tennessee, found instigators pretty evenly split between men and women. This is notable, given that almost all conventional murders are committed by men. But it tracks with the fact that women are almost as likely as men to wish someone dead. In The Murderer Next Door: Why the Mind Is Designed to Kill, David M. Buss, an evolutionary psychologist, reports that “91 percent of men and 84 percent of women have had at least one vivid fantasy about killing someone.”