I have a not-so-well-thought-out theory based on the series and a few things I've read about law enforcement in that part of the country, as well. I believe Steven Avery was a bad guy in a family of not so bright bad guys, and happened to be the one in that clan dumb enough to catch the heat for something one of his cousins did, not once, but twice. That, taken together with the same cops being involved in both of his arrests and convictions, the shaky evidence handling, and Brenden's ridiculously unethical original legal representation, at the very least there was more than reasonable doubt either was guilty.

 

One thing is certain, economic status has a lot to do with one's chances of getting fairly tried.

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