California’s Department of Labor Standards Enforcement website explains that a non-union employer has full discretion: a) to close the business on any holiday; b) to give employees the day off for any particular holiday; or c) to pay employees taking a holiday off. In this state, hours worked on holidays are not considered differently from any normal work day. Thus, as long as no overtime is involved, the law does not require any extra rate of pay for holiday work.
Union employees may have special terms under collective bargaining agreement. Many employers may provide (and thus must provide) holiday pay by policy but, again, it is not a legally required benefit.
Contact an experienced employment law attorney if you would like assistance issuing a policy covering time-off and pay for holidays.