The Constitution grants Congress substantial powers, including the ability to impose taxes, regulate interstate commerce, raise armies, and make all laws “necessary and proper” for executing its enumerated responsibilities. In order to exercise these powers, Congress must overcome formidable collective action problems. While some of these are caused by chamber size, others are caused by the incentives members have to be individually responsive at the expense of collective responsibility. These incentives help explain why Americans generally have a relatively high opinion of their own member of Congress but a low opinion of Congress as a whole.

The power and policy goals of individual members are dependent on their ability to win reelection at regular intervals. In the nineteenth century, members’ electoral fates were tied to the collective reputation of their party. Since World War II, a more candidate-centered pattern of electoral politics emerged, where candidates operate as independent political entrepreneurs. Congressional incumbents have taken advantage of this loosening of party ties, voting themselves staff and other resources for building substantial personal followings. While partisan behavior has resurged in the last few decades, these advantages of incumbency remain.

Inside the House and Senate, members face pressing information needs, coordination problems, transaction costs, and time concerns. Over time, party organizations and committee systems have evolved to help members deal with these challenges. The committee system improves decision making through the division of labor and specialization. Members give up the ability to affect policy in all jurisdictions while retaining influence in areas under the control of their respective committees. Parties serve as ready-made coalitions in an institution that makes most decisions via majority rule. In delegating authority to party leaders, members cede some measure of individual autonomy and face the possibility of agency loss.

Differences in the lawmaking procedures used in the House and Senate reflect the different sizes of the two chambers and respective terms of its members. In the House, the majority party is firmly in control, stacking committees with majority party members and using rules to pursue legislation favored by its members. In the Senate, individual members are better able to hold up the process, which leads to lower conformity costs but higher transaction costs. The intricacy of the lawmaking process gives opponents multiple opportunities to kill a bill, creating a strong bias in favor of the status quo.