In short:
I watch a lot of documentaries. I enjoy many of them but think few of them are 10/10 great. This is one of those few. You really need to watch all three episodes.
The long version:
When I consider a documentary to be art (as opposed purely entertainment), my enjoyment of it has very little to do with the topic and everything to do with the way in which it is presented. Especially when tackling an emotionally and politically-charged topic, a documentary should not set out to support one "side" or another. A good documentary aims to explore a complex topic by helping us understand the commonality of human nature driving seemingly-contradictory facets of an issue. A great documentary is one that goes beyond this individual human level by layering the narrative within a larger historical and societal context that further deepens our understanding. Great art not only makes us think, but also makes us feel. Navajo Police Class 57 is both a great documentary and great art.
To the user who wrote a previous 1/10 review:
I completely relate to your emotional reaction and feelings of disgust in watching many of the training scenes. I would guess (and hope) that most viewers shared those visceral reactions. I don't want to give any spoilers but I strongly encourage you to go back and finish watching all three episodes. I fear the following analogy might come across as glib and I hope you will take me at my word when I tell you that is not the spirit in which I intend it. To me, it seems that you wrote a review of the Navajo Police training process depicted in episode 1, rather than a review of the documentary itself. Giving a review of the series that is based on viewing only one of three episodes is akin to ordering an item online and giving the product a bad review because there was a problem with shipping and you never actually received the product you purported to review. Even if you need to look away and plug your ears during some of the disturbing training scenes (as I'll admit I sometimes do when watching something that elicits too strong an emotional reaction), I hope you will go back and watch all three episodes. I think you will come away with a more nuanced overall reaction to this documentary.
