Plot MCAT on the x axis and proportion of medical students who graduate within 4 years on the y axis. There is a steep curve that flattens out at about 26 (!) and dips slightly for the very highest scores (I suspect a small proportion of that group take a year off to do research & further buff their medical school credentials).
Have you ever heard of "driving while black?" Have you ever heard of other discrimination heaped upon blacks in the US? If not, you need to get to know more black folks.
Obviously there are racist practices that black people experience regardless of their socioeconomic status.
The magnitude of adverse experience should be determined by the essay written in the 'disadvantaged' portion of the AMCAS, rather than an otherwise uninformative checkbox in the race section of the AMCAS. I completely agree that an African-Am person growing up in Inglewood has significantly more disadvantage on average than an Asian-Am person growing up in a similarly poor (economically) community, and this is something that person could address in their essay.
But there is a certain level of adversity below which, even though environmental influences absolutely still exist, we ideally (imo, obviously) hold all people to the same standards. As a professional school, you are admitting adults (22 y.o.+) with free will.
Implicit in the argument that some groups have relative disadvantages causing their relative underperformance is that other groups have relative advantages causing their relative overperformance.
Taking the question of affirmative action from the other direction, the population with the most advantages is the Jewish population, which by measurement of financial and academic
far outperforms all other groups relative to their population. Should it be harder for a Jewish person to get into medical school relative to a non-Jewish white person (no data exist on this)?
What if Mr. Smith, in an underserved rural community in Montana, better emphasizes with Protestant doctors? Is it morally acceptable for a school in Montana, geared towards admitting doctors serving in its own state, to increase the level of difficulty for Jewish admits in order to have more Protestants more in line with the relevant populations?
As for the 26 argument, this can be addressed two ways.
1. 26 is the average for black students, which means 50% are below average. This represents a significant proportion of the population which has an increased chance of not finishing within four years. Excluding Puerto Rican (23.7 average, probably due to the PR schools),
no other URM group has more than 35% falling into this category (multiple Latino/Hispanic).
2. The MCAT gives you the opportunity for education and to take the USMLE. Whether or not score is relevant, students are told that scoring higher means more opportunity. The amount of future opportunities available is limited and therefore the admissions process is a zero-sum game.
In a zero sum game, favoring group A over group B is functionally equivalent to disfavoring group B relative to group A. I am sure you do not consciously deny anyone a spot in medical school as a result of race, nevertheless, that is exactly what is happening. Race is not the largest factor (the applicant's own responsibilities are), but it is one.
At the very least, any system that gives a subset of the population advantages or disadvantages based on their race must be absolutely transparent in its goals, as well as its methods and immediate/long-term results in relation to that goal. By its nature, affirmative-action-like policies is an ethical consideration that should be open for discussion by the community at large. A productive discussion on the degree of URM consideration given can only happen when the degree is known, rather than guesstimated.