Legal Question in Employment Law in California

I offer you two creative ways to attack this problem: 1) as a civil service employee you have certain rights to your employment as "property" and the government cannot take your property except by due process. Your approach can be: If you are going to take my services which are valued at "x" but pay me at the rate of "x-y," then you are taking my services without the set pay rate in violation of my rights to due process, whether I am Union or not. 2) Go to the employees and their Union Rep who are at the pay grade for this work, and let them know the City is passing off their work to a non-union CAII for less pay. They'll take the initiative to see that their work isn't being farmed out to a lower pay grade. In the meantime, you may want to do the work under protest, while pursuing your rights, in order to avoid being fired.

You are right. You should never perform work that your employer asks you to perform unless it falls within your specific job description. And when it comes time for a promotion or a raise, I am sure your employer will remember what a go-getter and team player you are and you will be first on the list.