Racial minorities are gong to be greatly overrepresented in a collection of mugshots, so it's almost certainly just the case that it's easier to make mistakes i

Racial minorities are gong to be greatly overrepresented in a collection of mugshots, so it's almost certainly just the case that it's easier to make mistakes in that direction. If the algorithm is, say, 99.99% accurate on faces that are the same race, gender, and roughly age, and there's 100 faces in there that match those, it'll correctly say no match .9999^100 = 99% of the time. If there's 5000, it's only going to find no match .9999^5000 = 60% of the time.