In this research note, we propose to complement the analytical toolbox for framing analyses with the categories of Aristotelian rhetoric. As our case, we analyse the function of the use of evidence in frame building in the context of Swiss direct-democratic campaigns preceding votes on smoking bans. Based on rhetoric, a frame can be considered to contain three interrelated elements: (1) political arguments (logos), (2) cultural symbols (ethos), and (3) emotional appeal (pathos). By comparing evidence-based arguments with arguments that do not refer to evidence, the research note illustrates that backing arguments (logos) by evidence increases their trustworthiness (ethos) but not their emotional appeal (pathos). We consider the Aristotelian categories a fruitful tool to enlarge existing framing research with regard to the use of evidence.