Legislative Power

According to Montesquieu's separation of powers theory, the legislative power is coequal to and independent of both the judiciary and the executive. Legislative power rests in a deliberative assembly with the tasks of debating, passing, amending, and repealing laws; raising taxes; and adopting a budget. Legislatures usually take final decisions in plenary sessions but are subdivided into various types of committees that may scrutinize government activities, including legislation, or conduct inquiries into specific matters.

This separation of powers doctrine more or less accurately describes power relationships in presidential systems, but in parliamentary systems executive and legislative powers are fused because the executive's capacity to govern depends on the parliamentary majority's willingness to support it. Therefore, in place of an institutional separation of powers, parliamentary systems are characterized by a functional division of powers between the government majority and the opposition.

Consequently, legislative power in parliamentary systems is effectively in the hands of the government. The government has the right to initiate legislation, including an exclusive right to introduce money bills. The role of parliament is to scrutinize government bills, which opens up an opportunity for the opposition to publicly present its alternatives to government action. In presidential systems, lawmaking is essentially the task of the legislature, which makes use of an elaborate system of committees and subcommittees. Winfried Steffani argues that it is not by chance that we use the term legislature for cases like the U.S. Congress whereas for European countries the term parliament (from the French parler, to talk) is adequate.

However, recent research has shown that power relationships in parliamentary systems vary considerably more than this simple typological distinction between parliamentary and presidential systems suggests. Using an extended database on parliamentary procedures and structures of European legislatures, Herbert Döring shows that the balance of power between government majorities and opposition parties in parliamentary democracies differs in the extent to which they can make use of procedures for setting the parliamentary agenda. His core finding is that the power of the opposition with regard to the timing of different parliamentary stages and the sequence in which amendments to a bill are voted upon are inversely related. To illustrate, in the British House of Commons, the government can make use of the guillotine motion to drastically reduce the amount of time spent on a bill but it does not have the so-called last amendment power. More generally, parliamentary systems differ dramatically with regard to the extent to which the executive branch has institutional prerogatives for controlling the content of bills and the conduct of parliamentary business. Seen from an agenda-setting perspective, the role of legislatures is often more relevant than the dualism between government majority and opposition in parliamentary systems seems to imply.