Study: Very small number of counties responsible for most executions

Only two percent of the counties in the U.S. have executed the majority of death row inmates since 1976, a new study finds.

This disparate use of capital punishment puts a large financial burden on the overwhelming majority of jurisdictions that do not kill inmates, because the process of convicting, housing and ultimately putting to death convicts is incredibly expensive, more so than simply locking them up for life, according to the study from the Death Penalty Information Center.

In addition to those inmates put to death, the study states that "only 2 percent of the counties are responsible for the majority of today's death row population and recent death sentences. To put it another way, all of the state executions since the death penalty was reinstated stem from cases in just 15 percent of the counties in the U.S. All of the 3,125 inmates on death row as of January 1, 2013 came from just 20 percent of the counties."

The study singled out Maricopa County, the area around Phoenix infamously policed by Sheriff Joe Arpaio. That one county has four times the number of pending death penalty cases per capita as both Los Angeles and Houston.

The study also pointed out that Philadelphia County in Pennsylvania ranks the lowest in the state in paying attorneys representing death row inmates, and it also has the third-largest number of inmates on death row in the country.

According to the study's authors, the report is intended to point out that seeking and following through on the death penalty is largely the work of a few driven prosecutors and district attorneys, often at great cost that they only bear a small part of.