| Name | Title | Court | County | Rate this Judge | Rating | # of Ratings |
| Hon. Kathleen O'Connor | Judge |
Superior Court
| Yuba |  | 9.9 | 7 |
| Hon. Joanne O'Donnell | Judge |
Superior Court
| Los Angeles | | 3.0 | 22 |
| Hon. Michael O'Gara | Judge |
Superior Court
| Los Angeles | | 9.7 | 1 |
| Hon. Mary Ann O'Malley | Judge |
Superior Court
| Contra Costa | | 3.4 | 1 |
| Hon. Robert O'Neill | Judge |
Superior Court
| San Diego | | | 1 |
| Hon. Vincent O'Neill, Jr. | Judge |
Superior Court
| Ventura | | 4.6 | 6 |
| Hon. Gail O'Rane | Judge |
Superior Court
| Riverside | | 1.2 | 15 |
| Hon. James Oakley | Judge |
Superior Court
| Madera | | 9.5 | 5 |
| Hon. David Oberholtzer | Judge |
Superior Court
| San Diego | | 5.6 | 7 |
| Hon. Ricardo Ocampo | Judge |
Superior Court
| Los Angeles | | | 0 |
| Hon. Frank Ochoa | Judge |
Superior Court
| Santa Barbara | | 4.1 | 1 |
| Hon. Hon. Gilbert Ochoa | Judge |
Superior Court
| San Bernardino | | 4.8 | 12 |
| Hon. Steven Ogden | Judge |
Superior Court
| Los Angeles | | 3.3 | 2 |
| Hon. John Oglesby | Judge |
Superior Court
| Kern | | 5.3 | 10 |
| Hon. Sam Ohta | Judge |
Superior Court
| Los Angeles | | | 0 |
| Hon. Vincent Okamoto | Judge |
Superior Court
| Los Angeles | | 2.4 | 1 |
| Hon. Dan Thomas Oki | Judge |
Superior Court
| Los Angeles | | 4.7 | 6 |
| Hon. Margaret Oldendorf | Judge |
Superior Court
| Los Angeles | | 8.3 | 14 |
| Hon. Robert Oliver | Judge |
Superior Court
| Fresno | | | 0 |
| Hon. Elizabeth Ufkes Olivera | Judge |
Superior Court
| Colusa | | | 0 |
| Hon. Charlaine Olmedo | Judge |
Superior Court
| Los Angeles | | 7.5 | 3 |
| Hon. Lynn Olson | Judge |
Superior Court
| Los Angeles | | 1.7 | 1 |
| Hon. Tomson Ong | Judge |
Superior Court
| Los Angeles | | 7.0 | 11 |
| Hon. Rafael Ongkeko | Judge |
Superior Court
| Los Angeles | | 5.5 | 16 |
| Hon. Charlotte Orcutt | Judge |
Superior Court
| San Joaquin | | | 0 |
| Hon. Adrienne Orfield | Judge |
Superior Court
| San Diego | | 2.5 | 1 |
| Hon. Tiffany Organ-Bowles | Judge |
Superior Court
| Kern | | | 0 |
| Hon. Lawrence Ornell | Judge |
Superior Court
| Sonoma | | | 0 |
| Hon. Delbert Oros | Judge |
Superior Court
| Sacramento | | 9.0 | 9 |
| Hon. Gary Orozco | Judge |
Superior Court
| Fresno | | 4.8 | 2 |
| Hon. Yolanda Orozco | Judge |
Superior Court
| Los Angeles | | 4.9 | 8 |
| Hon. Elia Ortiz | Judge |
Superior Court
| Napa | | 1.6 | 10 |
| Hon. Benny Osorio | Judge |
Superior Court
| Los Angeles | | 8.3 | 5 |
| Hon. Frank Ospino | Judge |
Superior Court
| Orange | | 4.2 | 9 |
| Hon. Peter Ottenweller | Judge |
Superior Court
| Sonoma | | 1.0 | 1 |
| Hon. James Otto | Judge |
Superior Court
| Los Angeles | | | 0 |
| Hon. Daniel A. Ottolia | Judge |
Superior Court
| Riverside | | 5.2 | 14 |
| Hon. Carol Overton | Judge |
Superior Court
| Santa Clara | | 3.5 | 16 |