When Sanford B. Dole retired as judge of the federal court in 1916, President Woodrow Wilson appointed Vaughan to fill the position.

[9] Her career was put on hold for several years after her October 7, 1935, marriage to US Navy captain Melbourne Newcomb Gilbert, who was stationed in Vallejo, California.

One of the cases she worked on was that of Honolulu doctor of naturopathy Hans Zimmerman, who challenged his arrest and detention with no charges filed against him.

In 1944, Wirtz became Circuit Judge, and with unanimous approval from the county board of supervisors, Honolulu mayor Lester Petrie appointed Gilbert the City-County Attorney, the first woman to hold that position.

One of her last cases put her at odds with the supervisors, who had followed territorial legislation and allocated funds for back pay to litigant county employee Llewelyn H. L. Hart, covering the period he had been suspended pending the outcome of legal action.

The backlash to her legal opinion was so intense that supervisor Nicholas T. Teves threatened to introduce a motion to have her fired.

[14] After resigning her position with the city and county, she went into private practice, and until 1967 contracted her services to the Honolulu Board of Water Supply.

[16] She played a key role in the legal career of Thomas Shoichi Ogata who went on to become a justice of the Supreme Court of Hawaii.

Based on her personal recommendation, he was admitted to the Hawaii Bar in 1945, and she appointed him as Deputy City-County Attorney.