The San Joaquin County Public Defender was established as a County Department in 1968. Public Defender Peter Fox (2008 - present) was preceded by James L. Larsen (2005 - 2008), Gerald L. Gleeson (1991 - 2005), Loren Mandel (1990) and Robert N. Chargin (1968-1989). The office is a major public law office, serving the county's 30 judicial positions in 5 locations, with 59 Attorneys, 17 Investigators and an Administrative Support Staff of 20. Public Defender Attorneys and Staff handle an incoming caseload exceeding 1800 cases per month.

The Public Defender's primary practice areas are:

• Adult Criminal Defense
• Juvenile Criminal Defense
• Child Dependency (focus on parents)
• Mental Commitment Defense
• Civil Extension Actions (§ 1026.5, W&I, § 1800 et.seq.)
• Expungement, Certificates of Rehabilitation

Public Defender clients are screened by court staff for indigency. County funded legal services are provided only on mandated cases to those who lack the present means to hire private attorneys. Lawyers Reference Service has a contract to handle cases because of conflict of interest (i.e., two individuals are arrested and charged with the same crime).