This is still my take on this:
Avery deserved a fair investigation, after what happened to him the first time. The local police recognized that they couldn't fairly perform this investigation and admitted this, unprompted, on record. They then shit all over that.
The people who found the evidence shouldn't have been anywhere near his property.
Just like if the police don't get an appropriate search warrant, you can't be found guilty based on evidence illegally attained, guilty or not, Avery was not afford due process, and guilty or not, should not have gone to prison.
The police were reckless, and desperate to stick this on a guy who they had already done massive harm to. So he should have walked free.
Who knows what would have happened if an untainted investigation was done. Maybe the same conclusion... but it will forever be tainted.
I mean, we're all meant to get due process. But Avery deserved it more than most.