Caselaw Visualizations

SCOTUS Opinions by Political Party

Relative Number of SCOTUS Opinions by Nominating President & Political Party

The following sunburst diagram depicts the number of opinions authored by the US Supreme Court Justices organized by their nominating president’s political party. The graph is built on data made available by the Harvard Law School Library’s Case Access Project (found at Case.Law). As such, it covers published federal cases up to 2018 with additional restrictions found here.

In other words, the diagrams below can answer the question:

Which political party's nominated Justices have been the most prolific?

Being prolific is defined by the number of opinions authored or coauthored by each Justice. When viewing the entire dataset, we get the following (potentially overwhelming) diagram. The Justices are labelled as:

Justice = "(Year Joining SCOTUS) Full Name, n=#Opinions authored or co-authored"

Below this diagram there is another version, which is interactive and only shows a subset of the data at a time for a more visually pleasing experience.

To navigate the interactive diagram, click on any party or president that you would like to see in more detail. To “zoom out” click on the center of the diagram.


To begin answering this question, I filtered the federal cases on Case.Law’s dataset by using the Supreme Court of the United State’s court ID number. I then analyzed each case’s opinion(s) to find their authors. Since many (if not all) cases in Case.Law’s dataset were scanned and then underwent optical character recognition, the dataset contained errors such as the following:

Justice Brandeis, for example, is referred to as:

"Mr. Justice Beakdeis", "Mr. Justice BeaNdeis", "Mr. Justice BhaNdeis", "Mr. Justice BkaNdeis", "Mr. Justice Brakdeis",...

Justice Peckham, as another example, is referred to as:

Justice Peckham is referred to as: ["Mr. Justice Peckhaai", "Mr. Justice Pbckham", "Mr. Justice Pecrham", "Mr. Justice Peckuam," ...]

Opinions written by each Court’s Chief Justice sometimes do not refer to the author by name. Rather they merely cite to the “Chief Justice,” or sometimes as:

"Ch. Justice.", "The Chief Justice.", "Ch.. J.", "The CHIEF JUSTICE:", "Tbe Chief Justice", "Tlie Chief Justice', 'C. J.:', "Ch.J.", "Chief' JuJlice.", "Cb. J.,", "Ch; J.', "Ch.' J.", "■ The CHIEF JUSTICE", "The. CHIEF .JUSTICE", "Ch. Justice,", 'Ch. J..", "The CHIEF'JUSTICE", "The CHIEF-JUSTICE", "The Chief Justice. .", ...

When this was the case, the date of the case was used to determine authorship. Because of these “noisy data” issues, the diagrams should be taken with a grain of salt. I worked to clean the data as much as possible, but there may still be erroneous or missing attributions.

Lastly, if the same justice was nominated twice by different presidents (e.g., for Associate Justice then for Chief Justice), the Justice is shown twice on the graph, as relevant. The Case.Law dataset from which this graph was built contains cases up to 2018 but seems to lack a complete coverage of cases in the 2010s.

This post is part of the Caselaw Visualizer Project. For a description of the dataset and the processes used to generate these visualizations, click here. The data was made available by the Harvard Law School Library’s Case Access Project (found at Case.Law). For information about me, click here.