Does every murder in the United States really cost society $17 million?

To put a price on murder, researchers perform a poll. They ask a nationally representative sample of people how much they would pay to reduce the incidence of homicide in their community by 10 percent. Then they can extrapolate how much society writ large would offer to stop a single murder.

The answer? For homicide and other forms of violent crime, Americans are willing to pay a whole lot. In DeLisi's study it is not the "victim costs, criminal justice system costs, lost productivity estimates for both the victim and the criminal" that make up the bulk of the $17 million cost, though all of those are included. It's the "estimates on the public's resulting willingness to pay to prevent future violence." That accounts for a bit more than $12 million per murder.

"That number sounds like a lot, but people radically change their behavior in response to violent crime," DeLisi says. "Think about the D.C. sniper case, for instance. When that happened, two people on a rampage changed the behavior of millions of people. It was not just the cost of the state spending thousands of dollars on extra patrols and traffic stops, and the cost of the 10 left dead."

Still, the $17 million figure sounds high to Cohen. Why? Traditionally, willingness to pay is considered one yardstick for determining the cost of murder—an alternative and more comprehensive measure than the calculate-all-the-costs-and-add-them-up method. Adding them together is counting twice, he says. Cohen and other researchers generally estimate the price of murder at $10 million to $12 million—just the "willingness to pay" number.

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