The UK Ministry of Defence (MOD) has closed hundreds of investigations into alleged ill-treatment of detainees by British troops in Iraq. This article probes one reason given for the closure of these investigations: the assertion (without further evidence) that the allegations were ‘less serious’, ‘lower-level’ or in the ‘middle’ range of severity. These terms usually appear without reference to international law, and are once defined with reference to the English criminal law of assault, so that investigations were closed if the alleged treatment resulted in less than grievous bodily harm. The MOD's terminology is wrong-headed and conceptually underinclusive: it fails to grasp the threshold of inhuman or degrading treatment in international human rights law (IHRL), and largely neglects the investigatory obligations in IHRL, international humanitarian law (IHL) and international criminal law (ICL).