The Journal Sentinel authors cite the fact that blacks and Hispanics who were searched were no more likely to have contraband than whites who were searched (22% in both cases) as argument against the notion that more frequent stops (and searches) of blacks and Hispanics can be justified on non-discriminatory grounds. They write:
After the stop, Milwaukee police searched the vehicles of black drivers twice as often as whites, or one search for every 12 stops. But police found contraband items in searches involving black drivers at almost the same rate as whites - about 22% of the time.
Garvey, as is his wont, announces that the case is closed.
The first question is whether the black and Hispanic drivers had more contraband. In other words, is there some justification in stopping more Hispanics and blacks. They did not! So, no, there is not.Both Garvey and the paper have it exactly wrong. The fact that blacks and Hispanics who were stopped and searched were just as likely as whites who were stopped and searched to have contraband suggests (even if it does not definitively prove) that the stops and searches were not racially motivated.
Here's why. If the Milwaukee police department were engaged in racial discrimination, i.e., stopping persons for "driving while black and brown" then would expect those searches to yield fewer arrests and seizures than the stops and searches of white drivers who have presumably not been selected for discriminatory reasons. Having stopped blacks and Hispanics for no reason but that they were blacks would be expected to yield fewer seizures of contraband among the population subjected to discrimination because there was no good reason to stop them.
The fact that this was not so - that the likelihood of finding contraband in the cars of black and Hispanic detainees was equal to that of finding it the cars of white detainees - suggests that the criteria used for detention was not discriminatory.
Remember these statistics do not show that blacks and Hispanics in general are no more likely than whites to have contraband in their vehicle. That data might support an inference of discrimination. The comparison here involves only those who were stopped and searched.
This is a fairly common misinterpretation of statistics comparing outcomes among different racial groups. To put it in another context, assume that the UW was discriminating against black applicants. One would expect those blacks who are admitted to have higher credentials than the average white admittee. If the credentials for both groups are the same, an inference of even handed treatment is supported.
I expect the sloppiness from Garvey. The paper should have dug a bit deeper.