a. Self-defence
Rights-based moral justifications for killing in self-defence presume that human beings have a right to defend themselves from unjust threats. We might imagine a situation where Sam, who is walking from his home to the local store, is attacked by Meg with a gun. Meg tries to shoot Sam in order to kill him and take his wallet. If Sam is fortunate enough, in wrestling with Meg, to turn the gun onto her, and thereby kill Meg, then a reasonable person should conclude that, all other things being equal, Sam was morally justified in killing Meg. That is, it is morally permissible for Sam to kill Meg in a situation where: 1) Meg has intentionally attacked Sam; 2) Meg poses a deadly threat to Sam; and 3) Meg does not have a sufficiently just reason for her attack on Sam. The defender (Sam) is permitted to kill the attacker (Meg) because he is entitled to protect himself from a threat that endangers his life unjustly. This is a straightforward example of justified self-defence. But it still raises important moral questions about how the moral justification of self-defence works. After all, if we accept that killing another human being is normally wrong then how does self-defence morally justify the act of killing in the hypothetical case above?
One method of justificatory reasoning for killing in self-defence is rights-based. A rights-based moral justification for killing in self-defence is grounded in the idea that a victim of aggression has a basic right not to be killed.113 That is, all human beings
have a right not to be killed by an unjust aggressor. David Rodin, for example, argues that a coherent explanatory account of self-defence can be constructed around the idea of personal rights.114 And he reserves the term “self-defence” for the right and act of personal self-defence.115 Rodin argues that self-defence is best analysed as a simple liberty to commit homicide in the defence of life. But he believes that one should not confuse this assertion with the claim that they contain, as a constituent element, claims against others.116 According to Rodin, the justification of self-defence consists in a
simple Hohfeldian liberty to commit homicide. The exceptional nature of which enables it to function as a genuine right within legal and moral normative systems. It does this, he suggests, by demarcating and protecting important interests and liberties of individual persons and providing grounds for future normative deliberation.117
In moral terms, Rodin suggests, self-defence is most appropriately classified as a justification, not an excuse, because basic self-defence is an act that falls outside the class of culpable homicide. Someone who kills in self-defence, he suggests, does not commit murder for which we exempt him of liability. Rather, the defensive nature of the act makes it fail to be an instance of murder at all.118 Rodin points out that it might be argued that, when a third party comes to the defence of a victim, their action is justified by the victim’s possession of the right of self-defence. But it is not
immediately clear to him how the fact that the victim has a liberty to kill the aggressor could justify a third party in taking the aggressor’s life.119 According to Rodin, the right to defend strangers and third parties is best seen as having its basis independently from the justification of the victim’s own right of self-defence. The right to defend one’s own life derives from one’s right to that life, whereas the right to defend a third party 114 Rodin, 2. 115 Ibid., 13. 116 Ibid., 33. 117 Ibid. 118 Ibid., 30.
derives from more general considerations concerning the duty to protect the good and the valuable.120 Rodin believes that the general duty to protect goods and values can
result in extremely strong duties to act if the end in question is extremely valuable (such as human life) and the costs of action to the subject very low.121
The protection of the innocent defender’s life is the goal of self-defence. But if the justification of self-defence is based on the right not to be killed then it seemingly fails because a human being (the attacker) is killed. Therefore, suggests Fiona
Leverick, a satisfactory explanation for justifying killing in self-defence based on a right not to be killed must demonstrate why the defender’s life can be preferred to the life of the attacker.122 In other words, what establishes the moral asymmetry between the life of the attacker and that of the defender? How is it that the attacker loses his right not to be killed? And what happens to the attacker’s right not to be killed that the defender can rightfully override it?
b. Rights forfeiture
A key issue for a rights-based account to explain, in order to justify killing in self- defence, is establishing what happens to the attacker’s right not to be killed. Generally, this is done by suggesting that the attacker somehow forfeits his right not to be killed when he threatens another person’s life. Suzanne Uniacke, for instance, argues that the use of force in self-defence does not violate its victim’s right not to be killed since, as individuals, we possess this right only insofar as we are not “an unjust immediate threat to another person’s life or proportionate interest.”123 She suggests that a unitary account of justified homicide in self-defence, as an exception to the general prohibition on
119 Ibid., 32. 120 Ibid., 38. 121 Ibid., 39. 122 Leverick, 44.
homicide, requires that any unqualified right not to be killed be conditional: our
possession of an unqualified right not to be killed depends upon our not threatening the equivalent rights of someone else.124
We might choose to accept the argument that an attacker’s right not to be killed is forfeited when he threatens the rights of others. But how might a person, who is
threatening others, forfeit his life? According to Miller, one approach might be to conclude that the right not to be killed is absolute, and it is always wrong to transgress it.125 The absolutist approach to the right not to be killed firmly holds that there are no circumstances where forfeiture is justified. At best, one might be excused for taking a life. Miller argues that an absolute right not to be killed would mean that killing in self- defence is never morally justified. But such an absolutist approach to the right not to be killed, he suggests, does not accord well with the intuition that an innocent person has the right to defend her life from an unjust attack.126 So Miller concludes that it is unlikely that the right not to be killed is absolute because this means there are no circumstances in which defenders are justified in killing attackers.127 Victims of the most heinous violent crimes, if they chose to defend themselves, would be considered blameworthy for the death of their attacker.
A second approach, according to Miller, says that killing in self-defence might be justified by cancelling the attacker’s right not to be killed.128 In this case, the attacker loses his right not to be killed because he attempted to murder the defender. Thus an attacker is judged as not deserving a right not to be killed because he has not respected the right not to be killed of others. But the problem with this approach, argues Miller, is that it is not clear how or when (or even if) the attacker regains his right not to be
124 Ibid., 213. 125 325. 126 Ibid. 127 Ibid.
killed.129 We might imagine a scenario where the attacker – whose right not to be killed is cancelled because of his unjust attack – fails in his attempt but is also not killed by the defender. Having now lost his right not to be killed in this one case, the cancellation of his right not to be killed means that it remains morally permissible for anyone to kill him at any time. This is unreasonable. But having failed to respect the right not to be killed in others, how does he get his right not to be killed reinstated? And if he does, when does it come back? Is he required to earn it back in some way?
A third option is to override the attacker’s right not to be killed because it has been discounted in some way. According to Fiona Leverick, this approach attempts to override the attacker’s right not to be killed by discounting the life of the attacker. The life of the defender is preferred, she suggests, because the value of the attacker’s life has been reduced (or discounted) as a consequence of his moral blameworthiness.130
Although this approach solves the problem of permanent forfeiture with the cancelling rights approach, it only accommodates cases involving one attacker and one defender. In situations where multiple aggressors attack one defender, argues Miller, eventually the sum of the “worth” of the attackers will outweigh the worth of the defender’s life.131
Finally, Miller argues that rights forfeiture should be based on the notion of a suspended right. This is when a right is suspended under certain conditions but not permanently cancelled.132 A suspendable right not to be killed is not absolute. Its loss is only temporary and it achieves this result without the need to discount the rights of the attacker. This makes it a more effective account for justifying the loss of an attacker’s right not to be killed. According to Miller, the attacker’s right not to be killed is forfeited insofar as he is a threat to the life of others. The attacker’s right not to be
128 Ibid., 326. 129 Ibid. 130 , 46. 131 Miller, 327.
killed is immediately regained once he ceases to be a threat.133 Rights forfeiture is made plausible by this notion of a suspended right. So it is permissible to kill an attacker in self-defence when he has temporarily forfeited his own life because he is threatening the life of the defender.