The historic examination of the U.S. Supreme Court’s agreement rates over 234 years provides a deep dive into the evolving dynamics of judicial consensus, insightfully charted by Adam Feldman in Empirical SCOTUS. Analyzing the court’s unanimity from the early 19th century to the contemporary bench reveals a significant decline in agreement levels among the justices, juxtaposing the near-unanimous decisions of the 19th century with today’s stark polarization.
From 1800 to the 1930s, justices showed an overwhelming consensus in their decisions, often agreeing 90-100% of the time. However, a notable shift originated in the 1930s and 40s, marked by Justice Oliver Wendell Holmes, Jr.’s regular dissenting stance, a practice later encouraged by Chief Justice Harlan Fisk Stone. These changes paralleled the division seen in the New Deal era’s conservative-liberal splits, a legacy continuing to this day with significantly more disagreement, encapsulated in current ideological divisions on hot-button issues.
The study reveals the absence of “bridge” or swing justices, once epitomized by figures like Justice Anthony Kennedy, who played central roles in pivotal cases by maintaining relatively high agreement indices across ideological lines. The current conservative-leaning court signals a reduction of such bridge-building figures, underscored by Chief Justice John Roberts’ early bridge-building, which has given way to a more ideological alignment.
Feldman’s analysis highlights contemporary dynamics: Justices now agree roughly 72% of the time, contrasting sharply with the 95% agreement typical of the 19th century. This divergence indicates greater predictability in court decisions based on appointments, with ideological alignment driving confirmation processes to become intense evaluations of potential future rulings rather than qualifications alone. For additional insights into this analysis, one can view the detailed visuals and comprehensive data provided here.