

Attacks against the civilian population or civilians by way of reprisals are prohibited.… The civilian population as such, as well as individual civilians, shall not be the object of attack. The civilian population and individual civilians shall enjoy general protection against dangers arising from military operations.API, Article 48 see also Rule 1, CIL Study. In order to ensure respect for and protection of the civilian population and civilian objects, the Parties to the conflict shall at all times distinguish between the civilian population and combatants and between civilian objects and military objectives and accordingly shall direct their operations only against military objectives.The principle of distinction requires parties to distinguish between civilians and combatants and between civilian objects and military objectives: The relevant treaty and CIL rules are as follows (direct quotations appear in italics):

However, this prohibition is not articulated as a war crime in treaties other than the Statute of the International Criminal Court, which allows for the prosecution of individuals using any protected person to render military objectives immune from military operations, or benefiting from such use, in international armed conflicts (IACs). Together, these rules make clear that the prohibition of the use of human shields-voluntary or involuntary-is absolute in IHL. certain claims of CIL status of certain rules are contested by certain states).

According to the International Committee of the Red Cross’s magisterial customary international law study, many of these treaty norms find expression in customary international law (CIL) across the conflict spectrum. These rules derive primarily from Additional Protocol I (API) of the 1949 Geneva Conventions, which governs international armed conflicts (IACs). To assist our readers interested in the phenomenon of human shields, I’ve produced a compilation of the relevant legal framework (additions/suggestions welcome!)
