Design matters: second chambers, cabinet formation, and constitutional reform

This chapter discusses the conditions under which semi-parliamentary government can be stable. It responds to two conjectures about “strong” bicameralism: that constitutional designers who prefer strong second chambers have to be willing to accept (a) either a presidential system of government; or (b) oversized and ideologically heterogeneous cabinets. Both conjectures are largely unfounded because they neglect that second chambers can be designed to be powerful in the legislative process, but permissive with respect to cabinet formation. The chapter measures second chambers’ “restrictiveness” with respect to cabinet formation as a neglected dimension of bicameral designs and uses the resulting indices to explain comparative patterns of cabinet formation and constitutional reform. A conditional logit analyses of cabinet formation in 28 democratic systems in the period 1975–2018 shows that governments’ potential control of a second-chamber majority only affects cabinet formation when the chamber in question is restrictive. A comparative analysis of patterns of constitutional reform and stability in twelve bicameral systems suggests that reducing the restrictiveness of a second chamber—rather than its democratic legitimacy or legislative veto power—can be sufficient to stabilize a “strong” second chamber.