You haven't proved it's a race issue versus a class issue. A judge is more likely to sentence a defendant if they are lower class. A black person is approximately 19% more likely to be convicted than a white person, but a man is approximately 165% more likely to be convicted than a woman….the bias is greater by a factor of eight. If you understand how statistics work, this means that if a white woman has a 100% adjusted chance (we’re doing comparisons, remember, and not tests, so this is valid) then a black woman has a 119% chance, a white man has a 265% chance, and a black man has (at least) a 315% chance. Thus, if we have the same number of criminals of each type at trial, if 10 white women are convicted the numbers will end up like so:

10 white women

12 black women

27 white men

32 black men

Source:

http://people.terry.uga.edu/mustard/sentencing

With exactly the same number of equally guilty people of each race/gender, we saw 22 women convicted….and 59 men. Big difference, eh? In fact, this factor alone gives us a prison population that’s 73%male and 27% female. That’s three men in jail for every woman, but still far from our 93/7, which is thirteen men for every woman.

We’ve made an assumption, though: men and women are given the same sentence. Turns out, that’s simply not true. Overall, women get 40% shorter sentences, which if use women as a baseline means that if women get 100% sentences, men get 166%. (There is of course also a race component, but we won’t worry about it here. Suffice it to say that the race component is smaller than the gender component.)

What that means is that if a woman gets a one year sentence, a man will get a 1.66 year sentence. What effect does this have on our prison population? Simple: it raises the number of men in prison at any one time by a factor of about 1.7. If we go back to our earlier set of people this means that if we’re counting in years and the average 100% sentence is one year, we’ll have the same 22 women in jail, but 98, not 59 men. How about we run the percentages again? This time we’ve got 82% men, or four to one. At the very least this means we’ve got either a third as many women in jail as we should, or three times too many men.