I think he's guilty and is exactly where he ought to be.
One of the biggest hurdles to get around, is how he used a fake name and tried to disguise his phone number using *67, when calling Halbach (several times). Her car and remains are found on his property shortly after. (that's not even considering the forensic evidence)
--> He used his sister's name, probably because she doesn't like him? You would have thought he'd use a made up name surely?and IIRC it's her (Barb's) car.
If you're going to believe he's not guilty, then you must;
- Believe the Police murdered Teresa Halbach, or arranged it. --> No you don't.
- Planted all of the forensic evidence. --> Most of it yes. Given the history with the previous lawsuit, there's certainly motive.
- Planted the Rav4 on Avery's land without anybody noticing --> No you don't
- Planted Halbach's purse, phone, camera and personal items 20 feet from Avery's door. --> Probably
- Manipulated the phone records to plant the calls he made to Autotrader. --> No you don't.
- Planted the bullet in his garage, along with (Halbach's DNA) fired from Avery's own gun (which had been impounded) --> DNA yes, but no known source and no bone.
- Made up statements from Avery's previous inmates saying how he wanted to build a torture chamber to put women in (motive?) --> Hardly credible.
- Made up the reports that Halbach already knew Avery, had met him before and was 'creeped out' by him (victim knows the killer) --> Of course he has used her services before. Nothing wrong with that.
The problem with all of the above, is that it seems from the documentary that the Manitowoc county Sherrif's department, is comprised of halfwits - which makes it extremely unlikely that they could pull off all of the above tasks without messing it up, the amount of people who'd need to be involved combined with the temptation to 'blab' to a reporter, makes it extremely unlikely that this is a conspiracy. It's not impossible - it could be, but for me, it's very very unlikely.