I don't think it was confirmed but it heavily alluded to that three of the jurors refused to deliberate at all and pressured the others into a guilty verdict.
I think that is the thing that really got me. He lied, under oath, and it was proven that he lied. Yet his testimony was still allowed to be heard by the jury. Absolute madness.
SPOILER
There's so many questions the prosecution couldn't seem to come up with answers for / seemed to be completely ignored by the jury:
Colburn flat out lying about him being told the make and model of the car etc.
Why wasn't the room-mate investigated? The room-mate who didn't report her...
Had an idea about spoilers:
SPOILER (highlight the white space)
Write some text in the white space, change the font colour to white. BOOM! SPOILER!
SPOILER
I finished it the other day and its just incredible viewing. Throughout the whole thing I just got the sense that Avery simply wasn't liked by the authorities and that was that.
I want to talk more in depth but am conscious of people having not seen it yet!
Not sure, is there a spoiler tagging...