The relationship of trust or distrust that binds citizens to politics is nurtured by a range of factors, which depend on the social position of citizens, the undermining of their interests by public policies, and their normative perception of the political world. Using qualitative material provided by discussion groups of somewhat politicized French citizens, this paper identifies the common arguments for political trust and mistrust. What the members of the discussion groups say expresses a relationship to politics that has been built up endogenously with a highly normative dimension, and which demonstrates an argumentative capacity based on various principles.