I read an article on the statistical analyses of the death penalty
vis a vis "race" many years ago which attributed the difference in
capital sentencing to the nature of the crime itself. That is to say,
if the crime were a murder "passion-related" or a crime committed
during an armed robbery. As I recall there was a difference between
the races on the perpetrators' rationale for killing the victim. The
courts view a murder of a person "caught in the act" with a
perpetrator's spouse differently than a robbery/homicide of kids
working the night shift at McDonald's. Whites apparently were more
often the victims when the crime was committed during a robbery or
burglary attempt thereby increasing the severity of the sentence.
This does not mean race was not a variable, only that there may be
some mitigating circumstances if one only views the statistical
anomaly.
On 16 Mar 2001 02:48:42 GMT, Elliot Cramer <[EMAIL PROTECTED]>
wrote:
>Someone had wanted a source for examples; I found this looking up Arnold
>Barnett in Google.com. He has other interesting examples.
>
>From http://209.58.177.220/articles/oct94/barnett.html
>Arnold Barnett
>
>The Odds of Execution
>A powerful example of the first problem arose in 1987, when the
>U.S. Supreme Court issued its controversial McClesky v. Kemp ruling
>concerning racial discrimination in the imposition of the death
>penalty. The Court was presented with an extensive study of Georgia death
>sentencing, the main finding of which was explained by the New York Times
>as follows: "Other things being as equal as statisticians can make them,
>someone who killed a white person in Georgia was four times as likely to
>receive a death sentence as someone who killed a black."
>The Supreme Court understood the study the same way. Its majority opinion
>noted that "even after taking account of 39 nonracial variables,
>defendants charged with killing white victims were 4.3 times as likely to
>receive a death sentence as defendants charged with killing blacks."
>
>But the Supreme Court, the New York Times, and countless other newspapers
>and commentators were laboring under a major misconception. In fact, the
>statistical study in McClesky v. Kemp never reached the "factor of
>four" conclusion so widely attributed to it. What the analyst did conclude
>was that the odds of a death sentence in a white-victim case were 4.3
>times the odds in a black-victim case. The difference between
>"likelihood" and "odds" (defined as the likelihood that an event will
>happen divided by the likelihood that it will not) might seem like a
>semantic quibble, but it is of major importance in understanding the
>results.
>
>The likelihood, or probability, of drawing a diamond from a deck of cards,
>for instance, is 1 in 4, or 0.25. The odds are, by definition, 0.25/0.75,
>or 0.33. Now consider the likelihood of drawing any red card (heart or
>diamond) from the deck. This probability is 0.5, which corresponds to an
>odds ratio of 0.5/0.5, or 1.0. In other words, a doubling of probability
>from 0.25 to 0.5 results in a tripling of the odds.
>
>The death penalty analysis suffered from a similar, but much more serious,
>distortion. Consider an extremely aggravated homicide, such as the torture
>and killing of a kidnapped stranger by a prison escapee. Represent as PW
>the probability that a guilty defendant would be sentenced to death if the
>victim were white, and as PB the probability that the defendant would
>receive the death sentence if the victim were black. Under the "4.3 times
>as likely" interpretation of the study, the two values would be related by
>the equation:
>
>
>
>If, in this extreme killing, the probability of a death sentence is very
>high, such that PW = 0.99 (that is, 99 percent), then it would follow that
>PB = 0.99/4.3 = 0.23. In other words, even the hideous murder of a black
>would be unlikely to evoke a death sentence. Such a disparity would
>rightly be considered extremely troubling.
>
>But under the "4.3 times the odds" rule that reflects the study's actual
>findings, the discrepancy between PW and PB would be far less
>alarming. This yields the equation:
>
>
>
>If PW = 0.99, the odds ratio in a white-victim case is 0.99/0.01; in other
>words, a death sentence is 99 times as likely as the alternative. But even
>after being cut by a factor of 4.3, the odds ratio in the case of a black
>victim would take the revised value of 99/4.3 = 23, meaning that the
>perpetrator would be 23 times as likely as not to be sentenced to
>death. That is:
>
>
>
>Work out the algebra and you find that PB = 0.96. In other words, while a
>death sentence is almost inevitable when the murder victim is white, it is
>also so when the victim is black - a result that few readers of the "four
>times as likely" statistic would infer. While not all Georgia killings are
>so aggravated that PW = 0.99, the quoted study found that the heavy
>majority of capital verdicts came up in circumstances when PW, and thus
>PB, is very high.
>
>None of this is to deny that there is some evidence of race-of-victim
>disparity in sentencing. The point is that the improper interchange of two
>apparently similar words greatly exaggerated the general understanding of
>the degree of disparity. Blame for the confusion should presumably be
>shared by the judges and the journalists who made the mistake and the
>researchers who did too little to prevent it.
>
>(Despite its uncritical acceptance of an overstated racial disparity, the
>Supreme Court's McClesky v. Kemp decision upheld Georgia's death
>penalty. The court concluded that a defendant must show race prejudice in
>his or her own case to have the death sentence countermanded as
>discriminatory.)
>
>
>
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