Thursday, March 5, 2015

FERGUSON MATH

The US Department of Justice (Eric Holder, Proprietor), yesterday released its report on the shooting of Michael Brown in Ferguson, Missouri. It's a schizophrenic document which completely exonerates Darren Wilson (the officer who shot Brown), while condemning the Ferguson police department itself for racially-biased and discriminatory practices. The bias bits, quoted widely in the press, consist of “gotcha” statistics with no accompanying analysis or attempt to place the findings in context.

One of the most touted of these statistical findings is that 93% of the arrests in Ferguson are of African-Americans, though the population is only 67% African-American. The (unspoken) conclusion to be drawn is that the Ferguson police often arrest black people because they are black and not because they are criminals. To put it another way, the implication is that the same behavior that would land a black man in jail will be overlooked if committed by a white person.

What the DOJ report does not mention, however, is the underlying assumption of this 93%---67% comparison. This disparity can only have a racially-discriminatory explanation if the crime rates for white people and black people are the same. This, in fact, is what the DOJ would have us assume---that the rate for crimes committed by black people and the rate for crimes committed by white people are the same. But they are not, of course. The crime rate for black people is about six times the crime rate for white people, and it has been this way in America for at least fifty years.

Over the years, crime rates for different races and ethnic groups vary. They also vary from city to city. They may also vary with respect to specific crimes. Since the 1960's, for example, robberies by blacks occur at eight times the rate as that by whites. The homicide rate for blacks is about four times that for whites. The crime rate for rapes is only twice as large for blacks as it is for whites. These numbers have been documented repeatedly, for decades, across the country by city and state and federal authorities. The idea that 67% of the people in Ferguson (i.e., the black people) commit 93% of the crimes there is hardly surprising.

Let's translate this with some numbers. Since 2/3 of the residents of Ferguson are black and 1/3 are white, let's say there are 2000 black people there along with 1000 whites. Now let's assume that Ferguson resembles America over the last fifty years and that the black crime rate is six times that for whites. Therefore, if there is one white criminal per thousand white people, there will be six black criminals per thousand black people. Thus, out of the three thousand residents we are assuming, there will be one white criminal and twelve black criminals. Blacks will be 12/13 of the criminals and will commit 12/13 of the crimes, and will probably represent 12/13 of the arrests. That's 92%.

The reason 93% of the arrests in Ferguson are of black people is that 93% of the crimes in Ferguson are committed by black people. There is no other plausible explanation.

Copyright2015MichaelKubacki