U.S. Executions Per Capita Have Been Falling for 400 Years
By Bryan Caplan
The death penalty has fallen into disfavor in recent years. But what’s the long-run trend? I’ve intermittently wondered about this for over a decade. Last night, I finally decided to check.
I found a time series of total U.S. executions from 1608-2002 here, broken down (roughly) by quarter-century. I found a time series for long-run population here. The numbers are irregular during the early centuries, with decennial censuses since 1790.
Since the periods for the two series don’t perfectly match, I just use the population numbers closest to the final year of each quarter-century of executions. For example, 1650-1674 had 49 executions, and the year closest to 1674 for which population data is available is 1670 (when population was 111,900).
Here’s what I found:
The decline in executions per capita is perfectly monotonic. Since executions are aggregated over quarter centuries, the pattern isn’t utterly amazing, but I was still shocked by its consistency. In historical perspective, capital punishment virtually disappeared over a century ago, when its incidence approached one-in-a-million per year. “Ideas have consequences,” you say? Perhaps, but executions were in rapid decline long before liberal opponents of the death penalty began their crusade.