By Matt Ford

After a seven-week freeze following Clayton Lockett’s botched execution in Oklahoma, three states executed three death-row inmates in less than 24 hours last week. Georgia, Missouri, and Florida had tangled with defense lawyers for months over the secrecy surrounding their lethal-injection cocktails and where they were obtained, a key issue in Lockett’s death. Florida also addressed concerns about its inmate’s mental capacity; his lawyers claimed he had an IQ of 78. The U.S. Supreme Court rejected all appeals, however, and the three inmates—Marcus Wellons, John Winfield, and John Henry, respectively—were successively executed without apparent mishap.

In addition to their fates, Wellons, Winfield, and Henry have something else in common: They are among the disproportionate number of black Americans to have been executed since the Supreme Court reinstated the death penalty in 1976.

In the three states where they were executed, blacks constitute a disproportionate share of the death-row population relative to the state population. In Oklahoma and Missouri, black Americans are overrepresented on death row by nearly a factor of four.

These states aren’t isolated examples. The national death-row population is roughly 42 percent black, while the U.S. population overall is only 13.6 percent black, according to the latest census. (The national prison population overall is roughly 39 percent black, according to the latest Bureau of Justice Statistics data.) Some individual states are worse. In Louisiana, the most carceral state in the Union, blacks are roughly one-third of the population but more than two-thirds of the state’s death-row inmates.

We’ve long known that the death penalty disproportionally kills people of color. David Baldus, a University of Iowa law professor, and his colleagues studied more than 2,000 homicides in Georgia in the 1970s and 1980s for evidence of bias. Their landmark research, known popularly as the Baldus study, found vast racial disparities in Georgia’s capital-punishment system.

A black inmate named Warren McCleskey, who had received a death sentence for murdering a white Atlanta police officer, challenged it before the Supreme Court in 1987 using the Baldus study, arguing that Georgia’s racially discriminatory system violated his Eighth and Fourteenth Amendment rights. Justice William Brennan, who opposed the death penalty in all circumstances, explained in his dissent why the statistical evidence mattered:

 At some point in this case, Warren McCleskey doubtless asked his lawyer whether a jury was likely to sentence him to die. A candid reply to this question would have been disturbing. First, counsel would have to tell McCleskey that few of the details of the crime or of McCleskey’s past criminal conduct were more important than the fact that his victim was white.

Furthermore, counsel would feel bound to tell McCleskey that defendants charged with killing white victims in Georgia are 4.3 times as likely to be sentenced to death as defendants charged with killing blacks. In addition, frankness would compel the disclosure that it was more likely than not that the race of McCleskey’s victim would determine whether he received a death sentence: 6 of every 11 defendants convicted of killing a white person would not have received the death penalty if their victims had been black, while, among defendants with aggravating and mitigating factors comparable to McCleskey’s, 20 of every 34 would not have been sentenced to die if their victims had been black.

Finally, the assessment would not be complete without the information that cases involving black defendants and white victims are more likely to result in a death sentence than cases featuring any other racial combination of defendant and victim. The story could be told in a variety of ways, but McCleskey could not fail to grasp its essential narrative line: there was a significant chance that race would play a prominent role in determining if he lived or died.