The legal and customary norms that govern the permissible use of lethal force by police are more restrictive than those that govern the use of force by military personnel. This claim is not terribly controversial. The question is why we hold this asymmetry in norms. In this talk I will highlight three contextual asymmetries that seem to offer some justification for the asymmetry in the permissions granted to police and military personnel. These three asymmetries impact one or more of the four criteria that must be met if use of lethal force is to be justified: Threat, Liability, Necessity and Proportionality, and so offer some moral justification for our current legal and customary norms. I will argue that while the norms governing the permissible use of lethal force in self-defense provide solid foundations for our current legal and customary norms in ‘traditional’ police and military operations, these foundations weaken as these contextual asymmetries break down. This leads to one of two conclusions: in cases where the context is sufficiently similar, preserving the asymmetry in legal and customary norms may be without moral basis. I will highlight two worries that arise from this conclusion and then conclude by suggesting an alternative idea: we may have reason to differentiate police and military use of lethal force from individual use of defensive force. The collective nature of police and military conflict may allow us to look beyond the norms for individual self-defense.