John White Preston (May 14, 1877 – February 18, 1958) was an associate justice of the California Supreme Court from December 27, 1926, through October 1935.

[5][3] In November 1926, Preston was elected as Associate Justice of the California Supreme Court for the remaining four-year term ending January 5, 1931, of Thomas J. Lennon, who died in August.

[9] In June 1935, Preston announced he would retire before the end of his term to serve as special government attorney in the Elk Hills naval oil reserves case, part of the Teapot Dome scandal.

[11] While on the Supreme Court, Preston is perhaps best known for acting as prosecutor at the 1930 pardon hearing of Warren K. Billings, who was convicted in connection with the 1916 Preparedness Day Bombing.

[17] His brother, Hugh L. Preston, was a judge of the Mendocino County Superior Court for 11 years, and in May 1931 was appointed by Governor James Rolph as an associate justice to the California Court of Appeal, Third District.