Yes, actually, it DOES make the officers responsible for Gray's death. Gray was not in the van of his own volition, and was handcuffed and shackled, rendering him incapable of balancing his body against any sudden turns, stops or bumps in the road, of which there seem to have been many.
Jailers ARE held responsible for preventing prisoner suicides, which is why such things as belts, shoe laces, any medications, etc. are typically not in cells.
You did not show that my factual statement on Gray's choice, or the followup deductive reasoning, was in error. Rather, gave irrelevant speculations on Gray being put in a police van, provided speculations on turns and bumps, and then concluded with confusion over what jailers (on a moral level) are responsible for.
The moral issue is not over those things in which Grey did not have a choice. However, he was "jailed" within the van because he made a choice to carry an illegal weapon - that was his choice. And within that context he still had an informed choice on his own safety, to either stay in his seat or prone on the floor, or to risk serious injury by standing while shackled.
The direct causative agent was Gray's act of volition. There seems to be little evidence that his seeming choice to stand was coerced or forced upon him just because he was in the van or because of fraud; there was nothing lost by Gray in staying seated or prone on the floor.
IF he had been forced to stand because of being brutalized by 'a rough ride', or because he was told it was safe to do so, THEN you have a moral point to build on. But no evidence of such was introduced. (Nor is there any evidence that the injury occurred while prone or seated).
Finally, jailers are not MORALLY responsible for preventing prisoner suicides. That the law wishes to take away the right and ability of the prisoner to commit suicide is, in part, a dubious moral restriction. No one is morally compelled to stop an adult from making risky choices that might cause his/her death. There may be reasons to keep a prisoner from taking their own life, but 'for their own safety' is not one of them (and preventing such by restraint is often inhumane).
You are extremely confused if you think that this is about Porter being made to stand when bound. It was Gray who was bound. You have zero idea what happened in the van, aside from the fact that it involved sufficient force to cause GREY's death.
You are frankly just confused.
And you are either confused, snarky, (or not serious) if you actually think, after my numerous posts and cites on Gray and Porter, that this "slip of the tongue" is anything other than just that - whether you spell Gray underlined and bolded as "GREY"...or not.
Finally, if we are ignorant of what happened, you shouldn't be charging an assistant to the driver with involuntary manslaughter based on "speculations".