State switching from use of force to medical experts

Prosecution better hope they do a better job than the use of force experts did

This "should" be the prosecution's bread and butter and "should" actually be where they hope to finally establish a cause of death that makes sense to their case? Questions will be whether their original line of questioning has changed any since the use of force experts have pretty much undercut the theory that Chauvin administered a "choke hold". 

I would have probably expected that at these some of these witnesses are there to largely undercut the theory that George Floyd died of a drug overdose. However, the first witness called seems to be more of a respiratory and ventilation guy, meaning he will probably be testifying as to why he believes it was strangulation.

Will we hear more about positional asphyxia from this guy?

Update: We are only a few minutes into this testimony, but it certainly appears that this witness is testifying to something more akin to the positional asphyxia than any sort of neck strangulation. While he is providing a lesson on neck anatomy and is claiming (incorrectly based on the other witness testimony) that the knee is on the neck, it appears to be just one part of the greater reasoning for why Floyd suffered from asphyxia.  

Tobin is suggesting that the knee pressure applied to the back of the neck can cause a blockage of the hypopharynx. I don't believe that this particular reasoning was part of either of the two autopsies. In fact, the original autopsy made the point in saying that there was no physical evidence of damage that would consistent with this sort of strangulation death. 

There have been quite a few sidebars, most called by the judge. Exabits are being offered that had not been previously provided? Shocking!! 

Update: I will say, the most impressive thing about this particular doctor is his ability to accurately measure the CO2 rate, heart rates, and other vital body function measurements all from watching video. Not like they had a CO2 monitor or heart rate monitor on Floyd while he died to actually know any of this. In fact, at one point he even suggested that the ER doctor (who personally examined Floyd) was likely wrong about some of this based on his own personal findings.... from viewing a video. Amazing stuff. 

Too bad we could not clone this guy and have these clones of him just watching patients. Wouldn't even need to be there. Could monitor multiple patients from one location via close circuit. Imagine how much money they would save on all that expensive equipment hospitals use to track these sorts of vitals. 

Final update on doctor Tobin: I might argue that all in all this was the best actual witness so far for the prosecution. At the very least he attempted to provide an opinion that it was the police officers who killed Floyd, something that other witnesses were never even asked. That being said, this particular doctor seems less inclined to blame the knee as the major contributor, rather suggesting that a variety of physical factors led to his death. I believe this is part of an overall shift in strategy for the prosecution who are looking more at "positional asphyxia" than the death occurring direction from strangulation or the knee. The idea of positional asphyxia is not entirely new (the paid autopsy does suggest that factors other than the knee were in play) - but I believe that the deemphasis on the knee to the neck is a required strategy at this point.  

Update Doctor Smock: Didn't like this guy as much as the previous doctor. Perhaps because of the repetitive nature of the question and answer. Seems much like how the prosecution asked multiple people at the scene the same questions, perhaps they plan on asking multiple doctors the same questions. Obviously this provides the defense the same chance to ask the same questions and look for any differenced between the testimonies that could cause reasonable doubt that one or the other is wrong.

So while it can be an effective strategy to have multiple people beat down the same points, it comes with risks from a prosecutor's standpoint when you are attempting to keep a lid on "doubt". Unless your witnesses are totally in sync, it can cause issues with which one is right and which one is wrong. There is no such thing as good doubt for he prosecution in a trial.