 The uneasiness that appellate courts display when expert witnesses testify about multiple references classes is understandable. Perhaps, the reference class most favorable to the defendant should be selected, giving the accused the benefit of the doubt. This might be appropriate in some cases. But suppose the random match probability associated with a DNA match is 1 in 10 for people in group A, while it is 1 in 100 million for people in group B. Always going for the reference class that is most favorable to the defendant will in some cases weaken the incriminating force of DNA matches more than necessary.