He graduated from San Gabriel High School and then received a Bachelor of Arts degree in political science from California State University, Los Angeles in 1972. He then attended the McGeorge School of Law and earned his Juris Doctor in 1976.
From 1984 to 1997, Sandoval served as a Los Angeles Municipal Court commissioner. In 1997, he was selected to serve as a Los Angeles County Superior Court commissioner. While a Superior Court commissioner, Sandoval presided over the high-profile lewd contact case against Hugh Grant in 1995.
On July 11, 1995, Sandoval sentenced Grant to 2 years probation and fined him $1,180.
Sandoval was appointed to the Los Angeles County Superior Court by Governor Gray Davis in 2001. Sandoval was the first openly gay judge appointed by Davis and believed to be the first openly gay judge appointed in California in 20 years.
Sandoval served until his death in 2006.