This article discusses a rare instance of the highest national courts explicitly addressing traffic signs in their judgments or decisions. It critically examines the standpoint expressed by the Polish Constitutional Tribunal and the Supreme Court, according to which the basic traffic sign categories in Poland—obligatory, prohibitory, informative and warning—are not separable [e.g. prima facie non-normative signs can also be normative ]. These courts formulated this idea when addressing the legal question concerning the applicability of legal provision penalizing failure to comply (...) with a traffic sign to parking a car without paying a fee in an area marked by an informative sign that indicates the need to charge a fee for parking. The article analyses and criticizes the relevant standpoint of the Polish Constitutional Tribunal and the Supreme Court. It shows how many negative consequences can result from frivolous treatment and neglect of traffic signs. It also reconstructs some possible practical recommendations concerning not only traffic signs but also visualizations of legal rules in general. (shrink)