The process is intricate and complex.

Even so, Prelogar said she thinks the most important part of her job is the work she does before a case makes its way to the U.S. Supreme Court. That job requires her to decide which cases the government pursues while weighing input from multiple federal agencies and the presidential Cabinet, which includes the Vice President and the heads of 15 executive departments, who she noted do not always agree on a litigation stance.

"My client is the United States of America," she said. "It's not a particular person of the federal branch."

Representing the United States as a client is "somewhat amorphous," Prelogar said, and the job requires a distinct set of tools, including listening skills, intellectual curiosity and "a dose of humility," because a solicitor general is often required to learn new topics and legal issues as they percolate up through the appellate process.

As an example, Prelogar pointed to complex details of tax law that she had to master to argue Moore v. U.S., which resulted in the justices' 7-2 ruling in June that upheld the 2017 federal tax overhaul's mandatory repatriation levy. She also recalled facing off before the state of Texas in three separate legal battles before the U.S. Supreme Court.