Maybe not murder but definetly manslaughter.
Even if it was fentanyl and a bad heart that killed him, the cops did nothing to help him and actively made it worse for no reason other than spite by keeping their knee on his neck in a prone position.

Floyd was handcuffed and wasnt of any threat at that point, and if someone says they have trouble breathing; sit them up.
That's literally what you're taught here when I worked as a security guard. Never ever keep a man pinned on a prone position if they show signs of not breathing normally or telling you they cant breathe, Floyd did both, and the cops responded with nothing.

It was just cruel, and we dont know the outcome of his current medical emergency if they had simply sat him up. At the very least the cops would have cleared their names if Floyd died anyway.
Problem with American cops is that they are so entitled. pic related.