In this article, we analyse selected institutional, contextual and personal variables previously proven to have an effect on the level of democratic deliberation in representative bodies. Selected theoretical propositions were tested on a sample of statements derived from a series of parliamentary debates on the so-called Family Act (Marriage and Family Relations Act) that has divided Slovenian politics and society. Initially, the authors present the current state-of-the-art in the field on the basis of a brief literature review of key determinants affecting parliamentary debates. In the second part of the article, on the basis of empirical scrutiny of the exposed determinants the authors assert that the interplay of institutional and personal determinants impacts the level of democratic deliberation, whereby the personal component has proven to have the most equivocal and theoretically sound effect on democratic deliberation in the Slovenian parliament.