RACE AND THE ENFORCEMENT OF DRUG DELIVERY LAWS IN ...

Capitol Hill—e.g. census tracts 74 and 75—during the four-month sampling
period 110 ). 111
Specifically, the results of the observational study indicate that 9.1 percent of the
observed deliverers were black, but 30 percent of the delivery arrestees were
black. Thus, blacks were over-represented by about threefold relative to the black
share of those observed engaging in drug delivery in Capitol Hill. Expressed
differently, this comparison indicates that blacks are 3.9 times more likely to be
arrested for delivery of a serious drug in Capitol Hill than whites engaging in the
same behavior.
Because the number of both transactions and especially arrests are smaller in
Capitol Hill than downtown, the Z scores that measure the significance of this
discrepancy did not achieve conventional levels of statistical significance. 112
However, if we combine observational and arrest data from Capitol Hill and
downtown, the results indicate that blacks are highly significantly overrepresented
among those arrested in these two neighborhoods as compared to
those who were observed delivering drugs in same locales (see Table 16).
110 The results of the observational study indicate that observed drug transactions in the
downtown area (census tract 81) outnumber those in Capitol Hill’s Broadway corridor (census
tracts 74/75) per hour of observation by a ratio of 3.5 to 1. However, delivery arrests in the
downtown area outnumbered drug delivery arrests in the Capitol Hill area by 6.8 to 1. Thus,
there is evidence that the SPD concentrates its drug enforcement resources in the downtown
area, and under-emphasizes the Capitol Hill neighborhood, in a way that is incommensurate
with the distribution of even outdoor drug activity. If indoor drug activity were also considered,
it is likely that this estimate of the over-representation of downtown drug delivery arrests
(relative to the frequency of drug transactions) would likely be even larger: The results of the
second wave of the needle exchange survey suggest that a larger share of the drug activity
that takes place in Capitol Hill occurs indoors. Specifically, 26.7 percent of those who last
obtained a drug in Capitol Hill got it indoors; 15.9 percent of those who last obtained a drug
downtown acquired it indoors.
111 There were no purposeful drug delivery arrests involving marijuana in census tracts 74 and 75
during the four-month sampling period.
112 Z scores are based, in part, on sample size, and reflect the fact that larger sample sizes
ensure greater reliability.
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