Congress as a Governing Institution

The rules of the Senate emphasize minority power. The Senate is sometimes referred to as a unanimous consent chamber because in practice many actions, including the consideration of legislation, require the consent of every senator. Early in the Senate's history the need for unanimous consent was rarely exploited by opponents of legislation to block it. However, that changed as the Senate became more active in the twentieth century. In 1917 rules changes created cloture motions, which allow Senate supermajorities to end the filibustering tactics of a minority of senators. Since then, requirements for achieving cloture have been amended numerous times. In the early twenty-first century, three-fifths of the chamber (sixty votes) is needed to end filibusters on bills and treaties, while a simple majority (fifty-one votes) is needed on most executive and judicial nominations (Supreme Court nominees still require sixty). These requirements, however, still allow a unified minority party to block action, and since the 1960s the use of filibusters has risen sharply (see Figure 2). For instance, during the 113th Congress ( 2013–2015 ) there were 218 votes on cloture.

The separate rules of the House and Senate amplify their other differences and thus make legislative action even more challenging. Not only do the members of each chamber hold different policy opinions and priorities, but one chamber is able to pass strictly majoritarian legislation whereas the other must accommodate the interests of at least some members of the minority. The resulting gap in the policies produced by the two chambers adds to the difficulty of congressional action and prevalence of gridlock that is a consequence of the legislature's design.

Each committee has jurisdiction over a set of issues, and legislation introduced on those topics is referred to it for further consideration. Legislation can also originate within committees, where it is drafted by committee staff, marked up, agreed to by committee members, and then sent to the floor for further consideration. The ability to bottle up referred legislation, amend it to their liking, or create their own bills has traditionally given committees significant influence in Congress. In addition, according to research by Kenneth Shepsle and Barry Weingast ( 1987 ), the ability of committees to dominate conference committees (a means of reconciling House- and Senate-passed versions of the same bill) gives them a second chance to amend legislation related to their jurisdictions to their liking, or else kill it before it becomes law.

Because of their power, committee assignments are highly valued by lawmakers in both chambers. Committee assignment processes, run by the parties, largely enable members to obtain seats that allow them influence over the issues most important to them and their constituents. As a result, many committees are made up of what are called “high demanders.” For example, members on the agriculture committees tend to represent rural areas with many farms, and members on the armed services committees tend to represent areas with large military installations. The legislation emerging from these committees is often in the interest of these particular groups, and not necessarily that of the country. In addition, these same committees' members dominate oversight of executive-branch departments and agencies related to their jurisdictions, giving them significant influence over policy in that way as well.

Political parties also affect how Congress governs and its ability to do so effectively. Parties simultaneously add coherence and functionality to Congress's structures, while adding new complications that sometimes make governance even more difficult.

Parties add coherence by bridging gaps within and across the chambers. Representatives and senators, elected individually from distinct districts and states, have numerous incentives to work apart, but parties provide incentives for them to work together. As argued by Frances Lee ( 2009 ), members of a congressional party have collective electoral and power incentives to coordinate their action. Electorally, all members of a party benefit if the party is popular among the voting public, or if the other party is unpopular. They also benefit when their party is in power, controlling one or both chambers of Congress. Thus parties link members across the chambers, spurring coordinated action to boost their party's image or take and maintain control over Congress. Parties also aid action within each chamber. Prerogatives available to the majority include control over every committee and over which bills are considered and debated on the floor. These powers make it easier for action to occur.

But parties can also make action harder. The possibility of Democratic control over one chamber and Republican control over the other raises new impediments to action. When majorities are at odds with each other the space for the bipartisanship necessary for action is reduced. Binder ( 2003 ) finds that this situation— divided party control—is the most antithetical to a productive American political system. Additionally, parties increase the frequency of coordinated obstruction, while ensuring some measure of minority party representation in the legislative process. The use of filibusters in the Senate is largely a consequence of party politics. Minority party senators have incentives to work together to block the majority's actions, force concessions, or both.

Parties also empower leaders. Party leaders are delegated substantial authority to take action and lead their party, and they are deeply involved in nearly every important initiative. Party leaders take the lead in setting each chamber's agenda, determining their party's policy positions and priorities, and facilitating communication, the taking of cues, and consensus building among party members. In the House the majority leadership controls the Rules Committee and uses it to ensure their party dominates policy making on the floor. In the Senate the majority leader negotiates with the minority, takes steps to break filibusters, and maintains control over the floor.

Party leaders have impressive abilities to foster party unity and rely on various powers to do so. Leaders control the distribution of important resources, including committee assignments, campaign funds, and other perquisites, and can leverage them to reward loyalty and punish disloyalty. Party leaders can allow loyal members to have their bills considered on the floor while blocking action on the bills of less loyal members. As shown by James Curry ( 2015 ), leaders are also empowered by their superior information. Their large staff resources allow leaders to be better informed than their rank and file about important legislation under consideration, and as a result become sources of information and cues for their timestrapped members. Consequently they can influence what their members know and how they understand bills and issues, and keep them in line on important votes.

Since the middle of the twentieth century, party polarization has amplified the importance and influence of parties in Congress. A measure of the distance between the parties in terms of their roll-call voting records indicates that the parties in both chambers have polarized dramatically since the 1950s (see Figure 3). In the early twenty-first century, members of each party are more unified than they have been in over a hundred years, and the partisan conflict over policy proposals has become very contentious. Polarization has dramatically altered how Congress operates. For instance, it has led to the further empowerment of leaders. Needing better coordination to overcome the opposition, parties have delegated substantial authority to party leaders since the 1970s. Polarization has also influenced congressional processes. To make law, parties in both chambers have turned to previously uncommon procedures such as restrictive rules in the House, complex unanimous consent agreements in the Senate, and budget reconciliation, as covered extensively by Barbara Sinclair ( 2012 ). Polarization has also played a role in the increase in filibusters (see Figure 2). With more disagreement between the parties, the minority in the Senate has been more willing to use its prerogative to block action.

Party polarization has made it even harder for Congress to take action by making bipartisan coalitions more difficult to create. According to Thomas Mann and Norman Ornstein ( 2012