Conflict of interest
California State Bar Formal Opinion No. 1980-52 It is improper for counsel in a criminal case to represent a defendant where a previous client of that attorney's office is a witness against the new client and it is reasonably foreseeable that the confidences or secrets of the former client may be, or may reasonably appear to the client to be, used. http://www.calbar.ca.gov/Portals/0/documents/ethics/Opinions/1980-52.htm People v. Lopez (2008) 168 Cal.App.4th 801, 808.
California State Bar Fomral Opinion No. 1981-59 "It is improper for counsel to continue representing either defendant charged in two separate, unrelated criminal cases once counsel becomes aware that one of these defendants is attempting to become, or has become, an undercover informant against the other defendant." http://www.calbar.ca.gov/Portals/0/documents/ethics/Opinions/1981-59.htm
Conflict of prosecutor
United States v. Navarro (E.D. Cal. 1997) 959 F.Supp. 1273. continued appointment of deputy district attorney as Special Assistant United States Attorney beyond statutory four-year limit on appointment of local government employees to federal agency for work of mutual concern was jurisdictional defect.
Rupley v. Winkler (1956) 147 Cal.App.2d 168
People v. Pumar (2023) 95 Cal.App.5th 504
People v. Lastra (2022) 83 Cal.App.5th 816
People v. AWI Builders Inc. (2022) 80 Cal.App.5th 248
Schumb v. Superior Court (2021) 64 Cal.App.5th 973
People v. Bell (2019) 7 Cal.5th 70
People v. Pierce (2019) 38 Cal.App.5th 321
People v. Dekraai (2016) 5 Cal.App.5th 1110
People v. Bryant, Smith, and Wheeler (2014) 60 Cal.4th 335
Packer v. Superior Court (2014) 60 Cal.4th 695
People v. Trinh (2014) 59 Cal.4th 216
People v. Sy (2014) 223 Cal.App.4th 44
Spaccia v. Superior Court (2012) 209 Cal.App.4th 93
People v. Gamache (2010) 48 Cal.4th 347
Polanski v. Superior Court (2009) 180 Cal.App.4th 507
People v. Cannedy (2009) 176 Cal.App.4th 1474
People v. Dehle (2008) 166 Cal.App.4th 1380
People v. Superior Court (Humberto S.) (2008) 43 Cal.4th 737
Hollywood v. Superior Court (2008) 43 Cal.4th 721
Haraguchi v. Superior Court (2008) 43 Cal.4th 706
People v. Vasquez (2006) 39 Cal.4th 47
People v. Jenan (2006) 140 Cal.App.4th 782
People v. Petrisca (2006) 138 Cal.App.4th 189
Hambarian v. Superior Court (2002) 27 Cal.4th 826
People v. Parmar (2001) 86 Cal.App.4th 781
People v. Choi (2000) 80 Cal.App.4th 476
People v. Neely (1999) 70 Cal.App.4th 767
Millsap v. Superior Court (1999) 70 Cal.App.4th 196
People v. Millwee (1998) 18 Cal.4th 96
Lewis v. Superior Court (1997) 53 Cal.App.4th 1277
People v. Eubanks (1996) 14 Cal.4th 580
People v. Clark (1993) 5 Cal.4th 950, disapproved by People v. Doolin (2009) 45 Cal.4th 390
People v. Zapien (1993) 4 Cal.4th 929
People v. Merritt (1993) 19 Cal.App.5th 1573
People v. Lepe (1985) 164 Cal.App.3d 685
People ex rel. Clancy v. Superior Court (1985) 39 Cal.3d 740
People v. Lopez (1984) 155 Cal.App.3d 813
Love v. Superior Court (1980) 111 Cal.App.3d 367
People v. Municipal Court (1978) 77 Cal.App.3d 294
People v. Alocer (1991) 230 Cal.App.3d 406
Prosecutor as witness
People v. Hernandez (2003) 30 Cal.4th 835
People v. Donaldson (2001) 93 Cal.App.4th 916