This article proposes an alternative to the conventional way of deciding when a State may target or detain members of an armed group. Instead of asking whether there is an armed conflict between the State and the group, this article argues that we should look at the State’s justification for the use of force against the group or its members. In a non-international context, this justification is rooted in human rights law. For this reason the State is only justified in using force against individual members of non-state groups when it is necessary and proportionate to the defense of life or the restoration of public order. In non-international armed conflict (NIAC), the justification for the use of lethal force depends on the threat posed by individual fighters and the context where they are encountered. The article argues against the use of international humanitarian law to determine the substantive content of human rights law in NIAC, but suggests that human rights law must be interpreted in a context-specific way.