@snood,
Yep, the other other side of the argument is:
- (I believe) they get training in positional asphyxiation at their academy
- Floyd said 20 odd times he couldn't breathe
- bystanders kept telling them that he couldn't breathe
- anyone with a minimum of knowledge would realise kneeling on a neck restricts a persons ability to breathe
properly
- his struggles weakened over time, indicating that he was running out of breath
- at least one of them thought they should roll him on his side to ease his breathing, indicating it was a concern
- the had an obligation to use the minimum force necessary to carry out their duties (otherwise is excessive force)
- they owed a duty of care to ensure that he could breathe / maintain the necessities of life
- Chauvin felt a need to check for a pulse, indicating that his state of consciousness was a concern (of course they may not have seen that, or they may have presumed it was done because of concern for the drugs in Floyd's system + his stillness)
If the EMT & MMA fighter feared Floyd's death, then I'm not sure why they didn't identify their skills, and tell Chauvin that Floyd was at risk of dying (Rather than saying he can't breathe...I haven't read where they did, but if they did, it is much more damning of any police officer who heard it).
I don't think any rookie purposely goes out to particate in a slow homicide. The question that arises is whether or not they suspected that is what was being done (the other part of deciding guilt we all know - no one did anything to stop it). So as I see it, the issue of their guilt depends on both knowledge (of the risks of death) & care owed to the necessities of life - ie breathing (care owed depends on either knowledge or a reasonable suspicion of care being needed), rather than any other particular argument.
I think the prosecution will make a good case. I just don't think that it will be enough to overcome the doubts that will arise.