Variable conceptions of positivism exist, although at the heart of the notion is the assumption of the scientific ideal of ‘objectivity’ as it pertains to the individual and society. Despite much debate and criticism of positivism in criminology, contemporary modes of positivism continue to inform criminological research. However, this more recent positivism is not necessarily the crude, overt positivism associated with the eighteenth- and nineteenth-century modes, but a more sophisticated and insidious brand - ‘covert positivism’. Most recently, in the domains of forensic genetics, objective research and empirical methods are being used subtly to make claims about the nature of criminal individuals and populations. These forensic domains utilise modern-day biological and psychological scientific procedures to assess, predict and make conclusions relating to ‘criminals, deviants, and pathologicals’ at genetic and neuronal levels. Critiques of these approaches are presented, as these scientific interventions are paralleled with historical modes of positivism.