"Killing for justice" sounds to me a whole lot like killing for revenge. says toadfrog. I posed the question from which he quotes because the thread-title contains the concept of justice. The thread had had many posters offering their insights into whether or not they would kill and, if so, in what circumstances. Which is not quite what the thread is nominally about. Justice and justifiable have similar etymologies: I had imagined (incorrectly, I now see) that my allusion would be generally understood.
Well, toadfrog, I'd have thought that you, as a lawyer, would have known the difference between justice and revenge. Why does "killing for justice" sound a whole lot like killing for revenge when (I presume) gaoling criminals, fining them, banning them from driving, have no such connotation for you? You seem to equate judicial execution (killing for justice) with killing for revenge because the end-product of both is the death of a human being. Do you make the same equation of a gaol sentence with kidnapping, or of a fine with theft (similar end-products: loss of liberty in the first case and reduction of assets in the second)? It is the essence of justice that the punishment should fit the crime.