By John A. Lupton, Supreme Court Historic Preservation Commission
Illinois is one of 23 states in which its supreme court chooses its own chief from among its members, unlike the Supreme Court of the United States where the President appoints the chief justice. When P. Scott Neville succeeded Mary Jane Theis on October 26, 2025, he became the 123rd
chief justice in Illinois history — and the 79th person to hold that office since statehood.
During the first constitution (1818 – 1848), the Illinois General Assembly appointed all Supreme Court justices, including the chief, who all served “during good behavior.” William Wilson, who was appointed chief in 1825, remained in that position until 1848, and still retains the longest tenure of any Illinois chief justice at 23 years.
The second constitution (1848 – 1870) introduced a seniority-based system in which the justice having the oldest commission shall be chief justice. In this scenario, a justice could be chief for a long period of time, as long as he remained on the court. However, with frequent turnover on the bench during this short constitutional period, Samuel H. Treat (1848 – 1855) and John D. Caton (1857 – 1864) shared the longest tenures, each serving eight years as chief.
Illinois’ third constitution lasted 100 years (1870 – 1970). The constitution stated that the “Chief Justice shall continue to act as such until the expiration of the term for which he was elected, after which the Judges shall choose one of their number Chief Justice.” In 1873, the court made a rule that created a one-year rotating chiefship, determined by seniority. If two or more justices were elected on the same day, they would “determine seniority by lot.” An additional rule passed in 1897 required a justice to be on the Court for at least two years before becoming chief.
Because chief terms lasted only one year, nearly every justice who served on the Supreme Court between 1870 and 1970 became chief at some point. If a justice had a long tenure on the Court, he could serve as chief multiple times. James Cartwright and Clyde Stone each served as chief five different times over their nearly thirty years on the bench. In both 1940 and 1961, three different chiefs served in a single year due to deaths in office and resulting successions.
In 1964, Illinois adopted a new judicial article to the 1870 constitution. It continued the model of selection from “one of their number to serve as Chief Justice for a term of three years.” However, the Court eliminated the rule stipulating seniority for choosing the chief. When Ray Klingbiel’s three-year term ended in 1966, the justices chose Roy Solfisburg as the new chief, which was a departure from prior practice. In the rotational system, Robert Underwood should have been the next chief. When Solfisburg resigned from the Court in 1969, Underwood became the chief. During his tenure, Illinois voted on yet a new constitution, which adopted the 1964 article nearly in its entirety.
The first selection of chief under the new constitution was mildly contentious. Chief Justice Underwood, a Republican, did not seek another term as chief, noting the court’s 4-3 Democratic majority. Both Thomas Kluczynski and Charles Davis each received votes from their fellow justices but lacked a majority. Another ballot gave all votes to Underwood as a compromise candidate, and he served another three years as chief.
Since then, the Court has followed an informal, and mostly consistent, practice of choosing the longest tenured justice who has not yet been chief to serve in the role. While methods to choose the Illinois chief justice have changed over the course of 200-plus years, the important role of the chief has remained constant—to oversee all of the courts in Illinois and to set the agenda for the Supreme Court as a leader among equals.