Critics of capital punishment have long cited the arbitrary nature of the death penalty as a reason it should be abolished in the U.S. Who gets sentenced to death can depend on a variety of arbitrary factors, including ZIP code.

Too Broken To Fix , a report released earlier this month by Harvard Law Schools Fair Punishment Project, highlights 16 so-called outlier counties in the U.S. where defendants are disproportionately sentenced to death.

Of the 3,143 county or county equivalents in the United States, only 16 or one half of one percent imposed five or more death sentences between 2010 and 2015, the report states.