The Limits of Honest Judgment: The Reasonable Commander Test and Mistake of Fact

The Rendulic case is probably the first demonstration of the link between the so-called “reasonable commander test” in international humanitarian law (IHL) and the defence of mistake of fact in international criminal law (ICL). This chapter analyses the link between the reasonable commander test and the mistake of fact defence. After an outline of the legal reasoning in Hostage, it examines the origins, purpose, and operation of the reasonable commander test in IHL. It analyses the mistake of fact defence in ICL. The analysis supports the view that in cases where the reasonable commander test is applicable, mistake of fact will only provide a defence where the mistake is both honest and reasonable. On a policy level, this interpretation best comports with IHL’s objective to protect the victims of armed conflict. To hold otherwise would lead to a dilution of the precautionary rules set out in IHL, removing a key incentive for commanders to ensure they have done everything feasible to check the accuracy of the information on which they base their decisions to attack.