“He never killed a man that didn't need killing”

[Capt. Hamp Cox]

Whose grave stone was so inscribed?

[Russ T Chambers]

I was going to say John Wesley Hardin, but I think this was just something he used to say.  I'll have to go with Clay Allison as to having it engraved.  Pun intended.   

[Capt. Hamp Cox]

Haven't seen it myself, but I have it on good authority that it is, in fact, on Clay Allison's grave stone.  Also, I cannot attest to the accuracy of said inscription.