It's difficult to determine, because we are not mind readers. We don't know what caused the attack and the likelihood of it happening again. It could be good enough if they stay in the same place, don't appear like a thread and wait for the police to arrive.
You do know something in this case though, you know he's killed your friend. That much of his mind you can read.
Seems that a reasonable threat would still exist.
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I would have to look at the probability of them escaping. What is a reasonable probability? I don't know.
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You can't, not in absolute certainty. But that applies to every person.
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when it's dead
I think you've seen what I wanted to show you. The criminal justice system offers you the luxury of wishing away the death penalty. Without that infrastructure, you'd be hard pressed to avoid capital punishment.
Not a good analogy imo. In that situation (unless you don't care if your friend dies...) you don't have other option than to try and stop the person attempting to take your friend's life. You don't even have to kill him either - you could use a taser or paralize him in some other way. If you had the option to magically lock him behind bars, why wouldn't you do that instead? Also, if your friend is dead and you kill the murderer afterwards when he turns his back to get out of the scene, you're not defending anyone. Unless he comes to you and threatness you too, you're taking justice into your own hands.
You're taking justice into your own hands regardless. That doesn't change after the murder. I'll explain below.
It would be a revenge situation, because my friend would be dead already.
Could still be defense.
Another reason not to kill the killer is that I wouldn't have all the information about what happened and wouldn't be in a proper rational place to judge the situation in an unbiased and fair way. Emotions would be taking over, or at least be a great influence on my decisions of killing or not killing the attacker. What if my friend, whithout me knowing, had raped the attacker's daughter? Or if my friend had ran over the attacker's wife and kept driving? Or what if my friend had beaten the attacker for years while in college? I mean, I wouldn't be able to make a fair and just decision not knowing about everything that led to that situation so I wouldn't shoot the attacker unless he was also threatning to kill me.
If some of those cases were true, you're not justified in using lethal force to protect your friend either. Your friend is now the one without rights, not the attacker. You may be right to say that it's not a good analogy. It is difficult to have enough information to act in that instance. What is needed to draw an analogy is evidence, beyond a shadow of a doubt, that your friend is innocent, and that the attacker is a murderer when he kills your friend. Short of that, it's not a good comparison to the criminal justice system performing an execution.
So bear with me and pretend that you have that information, and then see where that takes you in the hypothetical. You do, after all, have this information for yourself. So you know when you're attacked whether you are innocent. You know whether this person is attempting to commit murder, and you know that they are without their right to life even if they fail.
I have an honest question in my mind for you. From what I understand of your posts on other threads, you have quite a few objections to the idea of the governemnt taking responsability for its citizens' healthcare or education for instance (which I comprehend), but at the same time you approve the idea that the state should have the ultimate power to decide who to kill and who to let live.
It's literally what government is for. It's not a matter of whether I trust them to get it right every time, I don't. But that is literally the function of government, to protect human rights. You don't make this statement any less threatening or difficult for me if you rephrase it to "ultimate power to decide who to incarcerate for ever and who to let walk free". It doesn't change the question at all. So this is not a capital punishment issue, this is a question about whether government can be trusted to protect human rights, and the answer is no, and that's why government needs a lot of checks and balances in place to prevent it from getting out of control.
It's one of the reasons why I don't think the state should prohibit euthanasia or abortion, when the parties involved consent.
Euthanasia is obviously not a protection of human rights, so yes the state should not get involved in that. For abortion, it very much comes down to how one obtains rights, and when. The same issue is at play for murderers. If the murderer has rights, he cannot be executed. If the fetus has rights, neither can it.
If the person being convicted has the option to decide, without coersion, between life in prison or death penalty, I see it as being more reasonable.
This is what I advocate. In my personal view, death is an appropriate sentence for many crimes (including murder). But pragmatically it should be reserved beyond those, because we know the state will make mistakes, and the opportunity for abuse exists. It's never
necessary for the state to execute someone, but in my view it is
permissible. I don't think it's a good idea in general. But I don't go so far as to call for the eradication of the death penalty. I see it as an important part of the efficient operation of the criminal justice system, and something that should really never be used unless the accused chooses to waive the alternative (life in prison).
I also think that we should do it via firing squad.