Abstract: Drawing on approaches used by Gillborn (2008), this article examines results from the most recent version of Australian national testing (NAPLAN) in Years 3, 5 and 9, operating since 2008. It analyses the inequality of achievement between indigenous and non-indigenous students in the States and Territories, with particular reference to New South Wales (NSW) and the Northern Territory (NT). It frames an analysis by using the concept of locked-in inequality, one element within Critical Race Theory (CRT) in education. Whilst there is an achievement gap between indigenous and non-indigenous students in all States, in the NT it is a staggering fifty percentage points or more in reading, writing and numeracy across all Year levels currently tested. This article argues that there has not been any significant change to indigenous education outcomes in comparison with their non-indigenous cohorts, since the introduction of government funded education in the NT. Locked-in inequality has been deep and long-lasting in the NT and unless significant changes take place, this is set to continue.