He was a member of the Stanislaus County Board of Supervisors from January 7, 2019, until his death.

He previously represented the 8th district in the California State Senate from December 6, 2010, to November 30, 2018.

He had also served in the California State Assembly, representing the 25th district from December 4, 2006, to November 30, 2010.

After graduating from Ceres High School, Berryhill attended California Polytechnic State University, San Luis Obispo.

[3][4] Berryhill's brother, Bill, represented the 26th district in the State Assembly from 2008 to 2012.