Real-world political discussions usually mix reason-giving and storytelling in complex ways, but the interplay between these practices remains essentially unexamined. This article builds a theoretical argument based on a systemic approach for investigating such forms of communication in institutionally organized forums and informal settings alike. It contends that generalizations should not be made about the role of giving reasons and telling stories for good deliberation. A distinctive analytical framework is developed for examining these practices when deliberation is high quality, low quality, or changing (high to low or low to high). Drawing on data about discussions on reducing the criminal responsibility age in Brazil in legislative public hearings and face-to-face groups, the analysis uncovers variations in the structure of reasons and stories and shifts in their functions in optimal and suboptimal moments of deliberation. By incorporating the pragmatic dimension of interactions into the analysis, this paper contributes to advancing comparative analyses in different contexts.