<p>Interesting stuff on using lethal force in self-defense. There’s no copyright on this page so I reproduced several paragraphs. It looks like this is an overall messy area.</p>
<p>Self-defense, lethal force:</p>
<p>The standard for use of deadly force is, predictably, higher. The general criminal law allows for the use of deadly force anytime a faultless victim reasonably believes that unlawful force which will cause death or grievous bodily harm is about to be used on him. Again, Pennsylvania law is generally consistent with this standard.</p>
<p>The faultlessness requirement does not mean that the victim must be pure of heart and without sin. It does mean that the right of self-defense will not be available to one who has substantially encouraged or provoked an attack. The general rule is that words alone are not enough to be considered a provocation under this standard, but there are exceptions. For example, saying ‘I am about to shoot you’ might well constitute sufficient provocation.</p>
<p>One of the circumstances which helps to determine the level of threat encountered by the victim is the nature of the assailant’s weapon (if any). As a general rule, anything which might be used to kill a person, no matter how odd, is considered a deadly weapon. Thus, a chair, a lamp or a screwdriver may all be considered deadly weapons. In some instances, the law will treat a trained fighters hands as a deadly weapon, but in order to trigger the right to self-defense using lethal force against such a person, the victim must, of course, know of the attacker’s special training.</p>
<p>U.S. courts are split with respect to an additional factor in the lawfulness of the use of deadly force in self-defense. A minority of jurisdictions require a victim to retreat to the wall if it is safe to do so, before using deadly force. ‘Retreat to the wall’ is generally construed to mean taking any reasonable and apparent avenue of exit. However, even minority jurisdictions do not require retreat under three circumstances. There is no duty to retreat from one’s own home, if one is being or has been robbed or raped, or if the victim is a police-officer making a lawful arrest. In 1996 the Pennsylvania Superior Court held that “although a person is afforded discretion in determining necessity, level and manner of force to defend one’s self, the right to use force in self defense is a qualified, not an absolute right.” Pennsylvania is a retreat jurisdiction.</p>
<p>Even an initial aggressor may be given the right to self-defense under certain circumstances. If the initial aggressor withdraws from the confrontation, and communicates this withdrawal to the other party, he regains the right to self-defense. Also, if the victim of relatively minor aggression ‘suddenly escalates’ the confrontation to one involving deadly force, without providing adequate space for withdrawal, the initial aggressor may still invoke the right to self-defense.</p>
<p>[Self</a> Defense Law](<a href=“http://www.ittendojo.org/articles/general-4.htm]Self”>Self Defense Law and the Martial Artist)</p>