The one exception is affirmative action; being Black or Mexican (it's not even really generally Hispanic, IIRC, just Mexican) or Native American has a quantifiable effect equivalent to like +10 LSAT, +.x GPA or something. It's quite unfair, IMO. But it's very mechanical. For example, undergrad school prestige matters only at the very margins. Better to have a 4.0 from rando state school and a 170 LSAT score than a 4.0 from Harvard and a 167 LSAT for most law schools.
There is a whole site where people post stats and admissions results that is central to people trying to go to top schools. Nobody was getting results that deviated greatly. The racial boost was also well quantified on there (you check a box if you're an applicable race).