This article argues that the British used the legal system to legitimise brutal actions during their counter-insurgency (or colonial policing) campaign to defeat rebels during the Arab revolt in Palestine, 1936-39. The law was (re)constructed to provide a veneer of legal respectability to actions carried out by servicemen operating in the field against Arab rebels, allowing for reprisals and punitive actions against Palestinian civilians, targeted by the British in their offensive against rebels who were often hard to defeat in open battle. Lawlessness was the law. Servicemen were guided by a legal system that meant that they could accept the premises of their government that allowed for brutal actions, and they could do so with all the energy of good bureaucrats obeying orders. It shows that the British repression of the revolt was brutal and included torture and atrocities, notably at the villages of al-Bassa in 1938 and Halhul in 1939. More generally, its examination challenges the idea of British ‘exceptionalism’ in repressing imperial rebellions – the idea that there was a more benign British ‘way’ of dealing with colonial revolts. It suggests, however, that while some level of brutality became systematic and systemic, atrocious acts were exceptional and, comparatively speaking, British forces were more restrained than other colonial powers operating in similar circumstances. It also raises the issue of regimental differences in counter-insurgency methods.