AB(C)“ oder „ROM“? Zur Operationalisierung von Mehrheitsverhältnissen im Bundesrat

The answer on the question whether divided government in Bundestag and Bundesrat is present or not depends significantly on the arithmetic application used and its operationalization. Research on German federalism currently uses two models for describing the partisan majority in the Bundesrat: "AB(C)" and "ROM". Their use leads to substantially different conclusions on how dependent the federal government is on those Länder governments partially consisting of parties which are in opposition to the federal level. Both models comprise basic deficits. In contrast, a "modified ROM-model" could represent the partisan majority arithmetic in the Bundesrat in the most realistic way.