The manual that was NOT allowed as evidence.
Thee manual that was ignored by the police chief when he lied saying that Chauvin was not trained to do that.
A long (1hr 45 minutes) but excellent (and unbelievable) documentary about the Floyd arrest, riots and trial.
One of the amazing parts to me was how the politicians jumped on the suffocation thing so quick. Then the coroner does his study and says something like “He didn't suffocate. What do I do now?”
Go to 51:13 of that documentary for the exact comments. I was pretty close with my recollection.