According to the FBI Arrest Reports (Crime in the United States, 2010, Table 49), of all rapists 60.8% are white and 36.5% are black. Whites are 63% of the US population and blacks are 12% of the US population. So the Black-to-“White” per capita rate ratio for rape perpetration, R, is found from
R = (36.5/60.8 ) (63/12) = 3.15
If we took that at face value, it would mean that black men are about three times more likely than white men to rape some woman or other. However, the FBI (and the Department of Justice generally) lumps Hispanic males into the “White male” offender group. Most (over 90%) of the Hispanics in the United States are mestizos; they are not whites.
Experience with jurisdictions in which mestizo crime has been tracked separately from white crime provides a rule of thumb to apply, when correcting crime percentages attributed to “whites” by the FBI or by the DoJ, in order to remove the erroneously combined mestizo group. The correction is to multiply the percentage of crimes committed by the combination of “whites and mestizos” by a factor of 3/4 to reach a usually very good estimate for the percentage of crimes that were committed by whites alone.*
Thus corrected, the actual White percentage of total forcible rapes is 45.6% (instead of 60.8%), and the Black-to-White per capita rate ratio for rape perpetration, R, is found from
R = (36.5/45.6) (63/12) = 4.20
The average black man is 4.2 times more likely to rape a woman (without regard to her race), as compared with the average white man.
There were 84767 rapes reported to the police in 2010. Of these rapes, we can estimate that 38654 were committed by white men, 30940 by black males, and 15173 by mestizo males. Of the 38654 rapes committed by white men, not more than 10 had black females as victims.
According to an older study (from 2000), 75% of sexual assault victims were white women, compared to 20% for black females and 3% for other races. If we assume that the same distribution exists for victims of forcible rape in 2010, then we can reach the following conclusions:
Since white-on-black rapes are so very rare, nearly all of the 16953 black females who were raped, were raped by black males. Subtracting those victims from the total victims of black rapists in 2010 leaves 13987 non-black women who were raped in 2010 by black males. If we attribute half of the rapes whose victims were neither white nor black to black rapists, then we’re left with 12715 white women who were raped by black males in 2010.
Of course, that figure is based on a tenuous assumption that I made about the congruence of percentage distributions from another time and for a somewhat broader category of offenses, but until I find statistics that are more fine-tuned in relevance, this will be the best I can do.
If there were ten** rapes of black females by white men in 2010, then the Black-to-White per capita ratio for the perpetration of interracial rape in the United States in 2010 was
R = (12715/10) (63/12) = 6675
*This correction works in the United States as a whole, in the present and in recent history. It doesn’t work for areas having percentages of mestizos that are significantly higher or lower than the US average.
**Ten rapes of black females by white men in 2010 seems to be the maximum estimate in crime statistical reports that I’ve seen. It could be fewer.