Tuesday, August 23, 2011

Capital Punishment Knowledge Gap

The depth of it, considering it is the ultimate sanction to protect the innocent from the evil aggressor, is often astonishing, as noted by the Crime and Consequences blog.

An excerpt, with links at the jump.

“The Concord Monitor has this interview with presidential candidate Ron Paul. He claims to have changed his view on the death penalty based on "study." From what he says, it appears that his study consists of lapping up the anti side's propaganda the way a dog laps up antifreeze, completely unaware it is poison.

“For example, "It's so racist, too. I think more than half the people getting the death penalty are poor blacks."

“What did he study to come up with that gem? The DPIC website?

“We don't have firm numbers on "poor," but we have reams of data on race. As of 12/31/09, the population of death row was 3,173, of whom 1,317 were black. (BJS, Capital Punishment in the United States, 2009, Table 4.) That is 41.5%, significantly less than half, but I won't quibble over the 8.5%. Far more important is the logical leap that this ratio somehow indicates racism.

“What percentage of murderers are black? It runs pretty consistently about half. For 2009 single-offender, single-victim homicides where the race of the offender is known, there were 6,631 total with 3,106 black perpetrators, 46.8%. (Sourcebook of Criminal Statistics, Table 3.129.2009.) Other years are similar.

“Given that the percentage of blacks on death row is about the same (actually a tad less) as the percentage of murderers who are black, how does Paul make the leap to "so racist"? Probably by falling for the Fallacy of the Irrelevant Denominator and comparing the percentage on death row with the general population. But the general population is 99+% nonmurderers and hence irrelevant to a calculation about race and the death penalty.

“You don't have to be a genius to recognize the correct denominator in this problem. You only have to think about it a little. By failing to do so, even while claiming to have studied the problem, Paul demonstrates appalling shallowness of thought.”