Erik Scott was already dead anyway...
I'm almost convinced that you right about that.
Mr. Scott was (from all accounts) a very good, bright young man.
But even heroes can succumb to long term usage of sedatives and tranquilizers. If no one stops them, they die. One way or another.
Someone should have been doing Scott's shopping for him, if descriptions of his difficulties in the store are true. (I see no reason to doubt them. Not even his girlfriend denies he was having problems)
Still, that final shot after he was on the ground, has nothing to do with Scott's problems.
Before you totaly buy into the findings of the inquest, you should remember that this is not like a trial were both sides of the story are presented. The inquest is like a grand jury, the only evidence presented is that which the DA wishes. He can nake the outcome to be what he wants.