I just watched this movie on Netfilx. Of course they hit the topic of race very hard, appropriately. But they barely mentioned the political parties and never mentioned responsibility at all.
They showed the KKK without mentioning it was a Democrat Party organization. They read the 15th Amendment to the Constitution (which guarantees everyone the right to vote) without mentioning it was approved along a strict party-line vote. (Dinesh D’Souza reported that somewhere, I think in his “Hillary’s America” movie.) There was only one little segment where they even mentioned the parties at all–where Republicans had to make threats to be allowed to vote, but the tally was doctored by Democrats.
Maybe they shaded the truth because if it had been accurate, it would have looked like a hit piece on the Democrats.