The aim of the paper is to contribute to the critical study of digital data use in education, through examination of the processes surrounding school inspection judgements. The interaction between pupil performance data and other (embodied, enacted) sources of inspection judgement is scrutinised and discussed with a focus on the interaction between people (in this case inspectors) and data in the forming of judgements. I look at the changing position, work and personnel of the Office for Standards in Education (Ofsted) in England, drawing on recent Economic and Social Research Council funded research, with an emphasis on changes in the basis of authority claims of personnel (who traditionally operated through elite social networks and knowledges) and the rise of data (especially in its new interactive forms) in order to illustrate how the demands and logics of data production and use influence the performance of authority in school inspections in England, and with some reference to wider developments in Europe.