Manuel was born in Oakland, California, grew up near Ward and Dohr Streets in South Berkeley, and was educated in the public schools.
[3][11] In March 1956, then-Deputy Attorney General Manuel announced that municipalities adding fluoride to public drinking water cannot be charged with practicing dentistry.
[12] In January 1976, Governor Jerry Brown appointed Manuel to the post of judge of the Alameda County Superior Court.
[19] Among his notable cases is the criminal prosecution against William and Emily Harris of the Symbionese Liberation Army on charges of kidnapping Patricia Hearst in 1974.
[20] In August 1977, Manuel wrote the 6 – 1 majority opinion that the trial court abused its discretion in denying the defendants' request for state-appointed counsel of their choosing.