A recurring theme of the debate about the development and use of autonomous weapon systems (AWS) into the future is how to ensure accountability for their use. There is a fear that in the future an AWS might be involved in a serious violation of international law but that no one could be held responsible for that violation. This has led many scholars to propose ways to bridge the perceived gap between the decisions of the operator of the system and targets selected by the device.

The chapter contributes to this debate by considering how the legal obligation of states to carry out a weapons review links with the high threshold that has been set for individual criminal responsibility for crimes triable before the International Criminal Court (ICC). It shows the importance of testing in the development and acquisition of AWS and how testing and its documentation through legal review are important ways of promoting accountability for the use of AWS.