You can accept that bias exists, while denying that it explains very much of the difference. Again I know nothing about NZ, but in places where I've seen numbe

You can accept that bias exists, while denying that it explains very much of the difference. Again I know nothing about NZ, but in places where I've seen numbers, you can invariably show that the amount of bias in policing/sentencing statistically significantly different from zero... but also that is explains at most a few percent of the differences in violent crime convictions.