While it has been widely reported that partisanship in the United States Congress is at an historic high, a new study finds [2]that despite short-term fluctuations, partisanship or non-cooperation in the U.S. Congress has been increasing exponentially for over 60 years with no sign of abating or reversing.
As The Study notes, [2] Americans today are represented by political figures who struggle to cooperate across party lines at an unprecedented rate, resulting in high profile fiscal and policy battles, government shutdowns, and an inability to resolve problems or enact legislation that guides the nation’s domestic and foreign policy.
Partisanship has been attributed to a number of causes, including the stratifying wealth distribution of Americans; boundary redistricting; activist activity at primary elections; changes in Congressional procedural rules; political realignment in the American South ; the shift from electing moderate members to electing partisan members movement by existing members towards ideological poles; and an increasing political, pervasive media.
The individual representative’s role in facilitating partisanship is less clear. Party affiliation significantly shapes a legislator’s voting record, so much that in some cases, a change in a legislator’s party affiliation results in an immediate and significant realignment of voting behavior towards the new party agenda. This change is too rapid to be attributable to contemporaneous changes in constituent ideology, indicating a disconnection between the representative and his or her constituency. Party leaders also ensure obedience by offering incentives such as the prospect of assigning a member to a favored committee or promoting legislation crafted by the member to reach final voting stages, i.e. bringing legislation ‘to the floor’. As many have concluded, much is at stake with this type of party-driven arrangement.
Despite party-level pressures, there are incentives for individual representatives to vote with members of the opposite party on issues that are specific to a district’s geography, such as aging populations, natural resource management, veterans’ affairs, or regional concerns. Moreover, regardless of party affiliation, pairwise relationships may form as a result of social interactions such as sponsoring bills, interacting with lobbyists, creating trust networks for communication, sharing ideas, garnering support for initiatives, negotiating provisions and sharing one’s own sense of ethics and orthopraxy. Vote trading, also known as logrolling, is another incentive for cross-party cooperation. Though difficult to quantify because vote trading discussions are not public information, these would result in increased inter-party cooperation on ideological votes.
But the division of Democrat and Republican Party members over time shows things are getting worse...
As co-operation collapses and disagreements soar...
As the study concludes:
Our analysis shows that Congressional partisanship has been increasing exponentially for over 60 years, and has had negative effects on Congressional productivity. This is particularly apparent in the steady reduction of the number of bills introduced onto the floor, suggesting that the primary negative effect of increasing partisanship is a loss of Congressional innovation.
This increase in non-cooperation leads to an interesting electoral paradox. While U.S. voters have been selecting increasingly partisan representatives for 40 years, public opinion of the U.S. Congress has been steadily declining. This decline [30] suggests that voters cast their ballots on a local basis for increasingly partisan representatives whom they view as best representing their increasingly partisan concerns, leaving few if any moderate legislators to connect parties for a more cohesive Congress. Elected representatives are increasingly unable to cooperate at a national Congressional level but are re-elected at least 90% of the time, reflecting an evasion of collective responsibility.
Voters might believe that highly partisan candidates will ‘tip the scale’ in one party’s favor. However, based on correlations shown here, a partisan candidate may lack cooperation needed to pass legislation. More moderate legislators may have a competitive advantage in negotiating for their party’s legislation.
A fundamental reversal of increasing non-cooperation, over time, might require either a change in local ideological perspectives (resulting in a selective shift to fewer partisan representatives), or a fundamental change in how the electorate votes (from concerns focused on party issues to concerns focused on global effectiveness).


