Born in Jacksonville, Illinois, Hamilton received a Bachelor of Arts degree from Stanford University in 1974 and a cum laude Juris Doctor from Santa Clara University School of Law in 1976.

[4] She became an administrative judge for the San Francisco Regional Office of the United States Merit Systems Protection Board from 1980 to 1985, and was a court commissioner for the Municipal Court, Oakland-Piedmont-Emeryville Judicial District from 1985 to 1991.

[2] On February 9, 2000, Hamilton was nominated by President Bill Clinton to a new seat on the United States District Court for the Northern District of California created by 104 Stat.

5089 following the appointment of Fern M. Smith as Director of the Federal Judicial Center.

She served as Chief Judge from December 17, 2014 until February 1, 2021 when she assumed senior status.