As mentioned elsewhere, the journal article on which this is based specifically found that the difference in rates among women was not significant enough to mak

As mentioned elsewhere, the journal article on which this is based specifically found that the difference in rates among women was not significant enough to make a statement about women arrest rates based on race. So the data provided in this article are based on a restricted sample size and it is challenging to make statements about the overall population saying that "white females are arrested at a higher rate than black females". That might be true but we simply can't be confident in saying that that is true unless more data is gathered. Speculation on why such a difference could occur is harder still.