Dfariswheel I do not think the legality aspect of it is in any dispute at all. You cannot throw a pencil at someone not in self defense without running the risk of grabbing a charge of some kind or other.
In other words, according to my county prosecutor, shoot at a person with rock salt or rubber buckshot if it isn't a situation authorizing deadly force, he'll indict you for a felony.
"if it isn't a situation authorizing deadly force" is the key there. Not sure why someone would only have rock salt for ammo, but if that is all they had and used it in a pure self defense situation, you would want to know its effectiveness especially for any legality's that arose after wards. Like a stun gun,rubber bullets etc etc all have went through rigorousness testing as they are commonly used by US law enforcement and have been proven to be lethal in some situations.
But say you went into a pure hd/sd scenario with rock salt shot thinking it was less then lethal and said bad guy died a few hours later in the hospital, is it worse on you to say you thought it was not lethal? You would be asked that question in the few hours prior to him passing on the initial questioning.
"Well officer he should come out of it fine, I only shot him with rock salt because I did not really want to hurt him to bad"
One could then say, well if you did not want to hurt him "too bad" then use of deadly force was not required as your life did not warrant protection with real rounds?
Though on your initial statement you stated you shot him with the rock salt to stop the threat knowing it would /could result in deadly force and he later died, imo you would lessen your risk of that hd/sd situation being turned against you legally.
Something like salt rock though and just for the sake of argument you take the legality and situations out of the equation all together, one persons test should not be the conclusion of it being lethal or not.
There are many other reasons why its legitimacy should be investigated. Accidental discharge damage, avoiding the creation of the myth it is not lethal. The first hint some idiot gets that it is a harmless round and you will see videos of said idiots shooting each other with them on youtube.
bot site tends to be steering those to believe it is a harmless round with lots of bark but no bite.