Several here have said that legal justification is not at all related to the tactics that a victim or defender might use during an armed robbery (I think that the word “conflated” was used a couple of times). This is not correct. Legal justification can and does, in fact, constrain the menu of tactics that are available to a victim or third-party defender.
Assuming that a person chooses to abide by the law then it constrains them in some ways (from a legal standpoint) but the earlier comments you made seemed to imply that if legal justification existed then the defender should go ahead and use deadly force.
It is certainly true that the lack of legal justification should prevent a law-abiding person from using deadly force, but the existence of legal justification shouldn't prompt a person to use deadly force if they feel it is reasonable to avoid doing so.
Is it reasonable to weigh the risk of injury during an armed robbery on the basis of perception or even real data regarding the risk of murders and other severe injuries committed during armed robberies?
Of course it is. A person should know the facts and then make a determination of how to respond to the situation based on the facts and the circumstances. If their determination is that it would be reasonable to avoid starting a gunfight during an armed robbery then that is almost certainly the best course of action given that the across the board odds of surviving a gunfight are much lower than the across the board odds of surviving an armed robbery.
Legal justification and tactics are inseparably intertwined, not "2 separate issues conflated together".
Tactics is all about the best strategy for achieving the goal--presumably emerging uninjured at the end of the incident. Legal justification is about not going to jail afterwards.
If someone makes me nervous and I think that there's the potential for them to be a threat, the best tactic would be to take them out so that I don't have to worry about them any more. So next chance I get, I walk up behind them and put a round in their head. That is EXCELLENT tactics. I have eliminated a potential threat with no risk of injury to myself.
But it is also premeditated murder and there is no chance that it is legally justifiable.
A perfect example where tactics and legal justification have absolutely nothing to do with each other.
Tactics and legal justification are separate issues and conflating the two will result in confusion--just as it has in this discussion. Legal justification places some overall limits on tactics (at least for people who follow the law) but inside those limits there is still considerable latitude to choose various tactics.
But when I talk about something being reasonable, I'm speaking strictly in the narrow sense of something that a "...reasonable, prudent person would construe..." to be reasonable in determining whether use of deadly force could be legally justified.
The problem is that the concept of 'reasonable' is NOT strictly constrained to being applicable only to legal justification. Tactics can also be reasonable or unreasonable and a person's decision to resort to a particular tactic may be reasonable or unreasonable independent of the presence or absence of legal justification.
...where does the robber cross the line where deadly force is a legally reasonable alternative, and therefore legally justified?
Armed robbery, in and of itself, is generally sufficient justification for the use of deadly force in self-defense. That's why your comments are somewhat confusing. This thread is about reasonable tactics/strategy in situation where deadly force is already justified.
Only if you believe that legal justification and the selection of tactics are separate and distinct issues.
Think of it like this. In sports, there is a playing field and there are rules. Players are constrained in various ways by the boundaries of the playing field and by the rules. Those boundaries and rules are like laws. Within the boundaries of the playing field and the rules of the game, legal justification exists.
Does that mean that the rules and boundaries are the same thing as the tactics of the game? No, the boundaries and rules place outside limits on the activities of the game, but there is still a wide range of latitude for choosing reasonable tactics without bumping up against the limits of the playing field or the rules.
Imagine the frustration and confusion that would be generated if, during a discussion of the tactics of winning a game, one discussion participant one kept interjecting that the players can't go out of bounds even though no one was suggesting that they should, implying that if the players stay in bounds and don't break the rules then there's really only one tactic that makes sense, claiming that the word 'reasonable' could only apply to staying within rules and boundaries but not to the tactics employed within those rules and boundaries, etc.
