Early career

In February 1903, Ellis helped reorganize Florida's Office of the Expert Accountant into the Office of the Florida State Auditor. In return, Florida Governor William Sherman Jennings appointed him as to the position.^[4] Ellis served as the state's auditor until February 15, 1904, when he was appointed as the 18th Florida Attorney General by Jennings, finishing the term of James B. Whitfield, who had been appointed to the Supreme Court of Florida.^[5]

Ellis was elected to his first full term later in 1904. While serving as attorney general, Ellis, a Progressive, contributed in the reorganization of the Florida Bar, transforming the organization from a simple benefit society to an active group of lawyers, publishing a legal journal and drafting court procedures.^[6][7]

Ellis did not seek reelection in 1908, opting instead to return to private practice. From 1911 until 1915, he served as the general counsel of Florida's Internal Improvement Fund.^[8]

Supreme Court of Florida

On January 5, 1915, Governor Park Trammell appointed Ellis to the Supreme Court of Florida.^[1] Ellis served a long and distinguished career on the court, with his dissenting opinion for State v. Daniel (1924) foreshadowing what would become gender equality, writing:

Eligibility to office does not rest upon considerations of sex, nor does woman’s qualifications for public service rest upon any assumed spiritual endowments, or beauty of soul, nor peculiar faculty for discerning the distinctions, with clearer perception between right and wrong than her male compatriot.

While on the court, Ellis served as the President of the Florida Bar from 1919 until 1920.^[9] In 1926, the Florida Constitution was amended to allow the justices to elect their own chief justice. In January 1927, Ellis became the first chief justice elected in this way, "because he was the member with the most seniority who had not yet served in that capacity".^[10] He served as the court's Chief Justice twice, from 1927 until 1929 and from 1937 until he retired from the court due to illness on November 1, 1938.^[11]

In 1935, Ellis delivered a speech titled The Spirit of Americanism to the Civitan Club of Jacksonville, Florida. Since the speech occurred on Confederate Memorial Day, Ellis invoked references to Robert E. Lee to stoke the flames against what he saw was the overreach of the federal government during the Great Depression, breaking with the progressive views of President Franklin D. Roosevelt in favor of the ideals of states rights, which would eventually turn into the Dixiecrat Party.^[12]