Other mistake: The film is about a gang of Confederate soldiers after the Civil War, so a black man in the gang would seem a bit out of place.
Continuity mistake: When Curly Bill is shooting up the town while drunk, he fires about 10 more rounds than his six shooter can hold without reloading, and still has a round remaining when he shoots Marshal Fred White. In the 1880 court hearing held after Marshal White's death, Curly Bill still had 5 rounds remaining in his pistol.
Continuity mistake: In the prosecuting attorney's speech in the first courtroom scene, the judge's house of cards is no more than 2 levels high (a base level with a peak) [0:2:20]. In the close-up shot of the judge, the house of cards changes to 3 levels high (2 base levels and a peak)[0:2:35]. When the scene focuses back on the prosecuting attorney, the house is back to two levels of height[0:2:39]. (00:02:20)