| Name | Title | Court | County | Rate this Judge | Rating | # of Ratings |
| Hon. Melissa O'Connell | Judge |
Superior Court
| Contra Costa |  | | 0 |
| Hon. Michael O'Gara | Judge |
Superior Court
| Los Angeles | | 7.1 | 3 |
| Hon. Jennifer Jean O'Keefe | Judge |
Superior Court
| Monterey | | | 0 |
| Hon. Mary Ann O'Malley | Judge |
Superior Court
| Contra Costa | | 2.7 | 2 |
| Hon. Karen O'Neil | Judge |
Superior Court
| Santa Barbara | | | 0 |
| Hon. Robert O'Neill | Judge |
Superior Court
| San Diego | | | 1 |
| Hon. Gail O'Rane | Judge |
Superior Court
| Riverside | | 1.2 | 16 |
| Hon. James Oakley | Judge |
Superior Court
| Madera | | 9.5 | 5 |
| Hon. Ricardo Ocampo | Judge |
Superior Court
| Los Angeles | | | 0 |
| Hon. Hon. Gilbert Ochoa | Judge |
Superior Court
| San Bernardino | | 4.8 | 12 |
| Hon. Melanie Ochoa | Judge |
Superior Court
| Los Angeles | | | 0 |
| Hon. John Oglesby | Judge |
Superior Court
| Kern | | 5.3 | 10 |
| Hon. Sam Ohta | Judge |
Superior Court
| Los Angeles | | | 0 |
| Hon. Margaret Oldendorf | Judge |
Superior Court
| Los Angeles | | 7.5 | 16 |
| Hon. Sarah Oliver | Judge |
Superior Court
| San Bernardino | | | 0 |
| Hon. Euketa Oliver | Judge |
Superior Court
| San Diego | | | 0 |
| Hon. Elizabeth Ufkes Olivera | Judge |
Superior Court
| Colusa | | | 2 |
| Hon. Charlaine Olmedo | Judge |
Superior Court
| Los Angeles | | 6.1 | 5 |
| Hon. Gregory Olsen | Superior Court Judge |
Superior Court
| Riverside | | | 0 |
| Hon. Gregory Olson | Judge |
Superior Court
| Riverside | | | 0 |
| Hon. Lynn Olson | Judge |
Superior Court
| Los Angeles | | 1.7 | 1 |
| Hon. Tomson Ong | Judge |
Superior Court
| Los Angeles | | 6.3 | 16 |
| Hon. Rafael Ongkeko | Judge |
Superior Court
| Los Angeles | | 5.5 | 17 |
| Hon. Rei Onishi | Judge |
Superior Court
| Sacramento | | | 0 |
| Hon. Charlotte Orcutt | Judge |
Superior Court
| San Joaquin | | | 0 |
| Hon. Tiffany Organ-Bowles | Judge |
Superior Court
| Kern | | | 0 |
| Hon. Lawrence Ornell | Judge |
Superior Court
| Sonoma | | 9.8 | 1 |
| Hon. Delbert Oros | Judge |
Superior Court
| Sacramento | | 9.0 | 10 |
| Hon. Gary Orozco | Judge |
Superior Court
| Fresno | | 4.8 | 2 |
| Hon. Yolanda Orozco | Judge |
Superior Court
| Los Angeles | | 4.3 | 12 |
| Hon. Elia Ortiz | Judge |
Superior Court
| Napa | | 1.5 | 12 |
| Hon. Joseph Ortiz | Judge |
Superior Court
| San Bernardino | | | 0 |
| Hon. Cathy Ostiller | Judge |
Superior Court
| Los Angeles | | | 0 |
| Hon. Peter Ottenweller | Judge |
Superior Court
| Sonoma | | 1.0 | 4 |
| Hon. James Otto | Judge |
Superior Court
| Los Angeles | | | 1 |
| Hon. Daniel A. Ottolia | Judge |
Superior Court
| Riverside | | 5.2 | 14 |
| Hon. Carol Overton | Judge |
Superior Court
| Santa Clara | | 2.7 | 25 |
| Hon. Murat Ozgur | Judge |
Superior Court
| Monterey | | | 0 |