I read, after watching, that Martin Scorsese and his co-scriptwriter rewrote the whole screenplay after they realised it had become a police procedural that was too focused on the white male characters.
If only they had stuck with that, it would have been a story with some tension. As it is, it still focused on the white male characters, but somehow seemed set on humanising their brutal and evil behaviour, on trying to give them a get out clause.
At least with a procedural, there could have been the sickening revelation that most of the white men in town were complicit.
Alternatively, a screenplay from Mollie's point of view could have been an absolute classic.