Leeson's example of human sacrifice is the Kond people of India who lived in the Eastern Ghats mountain range of India in the first half of the 19th century, "the most significant and well-known society of ritual immolators in the modern era" When the British encountered this group around 1835, they discovered that human sacrifice was widespread. The Kond population as a whole was several hundred thousand people. There was no central government, but many tribes that included several villages each. The villages often raided each other, stealing cattle, food, and tools.
At least once each year, and often several times, tribes would purchase victims--typically non-Konds. Some tribes would purchase only one victim; others might buy 20 or more. After a wild three-day festival, the victim would be killed in some ceremonial and brutal way that always ended with the victim being torn into pieces. Sometimes the crowd tore apart the victims. In other cases, the victims were drowned in pig's blood or beaten to death before being torn into pieces. Then a representative of each village would take a strip of flesh from the victims and take it back to the village, where it was cut into smaller pieces so that everyone had a piece to bury in their field.
According to Kond belief, a victim or meriah had to be purchased. They did not view criminals or prisoners of war as suitable for sacrifice. Also, the price was high. Leeson explains (citations omitted): "Konds’ unit of account was an article of such property they called a “life” (or gonti). A life consisted of property such as “a bullock, a buffalo, goat, a pig or fowl, a bag of grain, or a set of brass pots . . . . A hundred lives, on average . . . consist[ing] of ten bullocks, ten buffaloes, ten sacks of corn, ten sets of brass pots, twenty sheep, ten pigs, and thirty fowls.” Meriah prices were rendered in these units. And their prices were considerable. ... [A] single meriah cost a purchasing community “from ten to sixty” lives. This constituted a “very great expense attendant upon procuring the victims” for sacrifice."
This human sacrifice practices of the Konds raise many questions (!), but from an economic perspective, Leeson focuses on two: Is there a way it might make economic sense to reduce your own wealth? And if so, is there a reason it might make sense to do so by spending the wealth on human sacrifices, rather than just, say, burning up crops and livestock, giving away land, or destroying tools?
For the first question, Leeson argues that when the risk of conflict is very high, and there is no good way to protect property from attackers, then those who have property may have an incentive to
make themselves worse off. He writes: "In agricultural societies nature produces variation in land’s output. This variation creates disparities between communities’ wealth. Absent government, wealth disparities induce conflict between communities, as those occupying land that received a relatively unfavorable natural shock seek to plunder those whose expected wealth is higher. If conflict’s cost is sufficiently high, it is cheaper for communities to protect their property rights by destroying part of their wealth. Wealth destruction depresses the expected payoff of plunder and in doing so protects rights in wealth that remains." As a close-to-home example, Leeson points out that people who live in high-crime neighborhoods may choose to drive beat-up cars or avoid showing any wealth as a way of making themselves less of a target. Leeson writes: "The poverty displayed by some well-known groups — from Gypsies to ascetics — may reflect their members’ rational decisions to have more secure property rights in less wealth instead of less secure property rights in more wealth."
But if one wishes to destroy wealth, why do so by the method of high-priced purchase of victims for human sacrifice? Leeson suggests that unlike burning crops or some other method, the purchase meant that the sellers of the victims would carry the news of the purchase price far and wide. Thus, it was not possible to fake by destroying only a small amount of a crop. The festival around the sacrifice meant that the destruction was widely seen and acknowledged, and the news would travel broadly, along with being communicated via pieces of the victim to those who had not attended.
I have a hard time seeing Leeson's explanation as the only reason behind the Kond practice of human sacrifice. For example, it seems plausible that human sacrifice might also serve as a way of making ferocity acceptable and binding together the group, in societies that were often either attacking others or defending themselves. But an economic-based explanation for human sacrifice need not be the exclusive truth in order to be a productive part of a fuller understanding.
In my mind, perhaps the strongest point in Leeson's argument is that when the British were trying to stamp out the Kond practice of human sacrifice, for years they tried violent punishment and they tried reason, without success. However, what did work was when the British offered to provide the tribes with a guarantee of security and a dispute-resolution mechanism--in effect, with a centralized government authority--the Kond tribes were immediately willing to give up their practice of human sacrifice. This pattern certainly suggests that the tribes, at least, viewed the sacrifice as a way of keeping civic order.