The Royal Commission on Genetic Modification (RCGM) appeared to be a 'public debate'. It sought the participation of people from a cross-section of society according to its broad terms of reference, and invited input on 'options' for the nation. The majority of the public and special interest groups voiced their opposition to Genetic Engineering (GE). Despite this, the Commissioners proposed that Aotearoa New Zealand proceed with GE with 'caution'. (The recommendations included recommencing GE field trials and planning for releases of genetically modified organisms.) In this research I applied a multidimensional discourse analysis model to the RCGM to investigate if it was pre-determined in its findings. I analysed the social and historical context of the RCGM, its processes, and the consequential narratives in the texts produced by the environmentalists and the bioproponents who made submissions, and the documentation produced by the RCGM. I found that Enlightenment rationality, shaped the context of the Commission and, was reflected in the processes for 'Interested Persons' (the interest groups). This made it difficult for groups to articulate objections to GE that were based on non-scientific, holistic and alternative worldviews. Furthermore, I found that the RCGM's findings reflected the contestation of science evident in the debate between the environmental groups and the bioproponents. The creation of a utopian 'sustainability' discourse by the environmentalists, and their construction of this vision into a tenet called the precautionary principle, confronted the bioproponents' utopian vision of Progress guided by experts using neutral science. The bioproponents' response, to reject the precautionary principle and appropriate and redefine sustainability to mean sustaining Progress through GE, was mirrored in the RCGM' s findings. Thus, modernist rationality shaped the processes of the RCGM, restricting public participation and articulation of opposition to GE, ultimately pre-determining the RCGM in favour of GE.