California law provides for three distinct levels of civil service: state, county, and municipal/city. The requirements for state civil service are comprehensive; for municipal civil service the requirements are minimal. A city can establish practically any classification system it chooses. Cal. Govt. Code Section 45000 provides: "It is the intent of this chapter to enable the legislative body of any city to adopt such a personnel system, merit system, or civil service system as is adaptable to the size and type of the city. The system may consist of the mere establishment of minimum standards of employment and qualifications for the various classes of employment, or of a comprehensive civil service system, as the legislative body determines for the best interests of the public service."
Because of the liberal character of the law, a precise answer to your question would require a careful review of the city's civil service ordinance. However, one thing is clear from the general provisions of Section 45000: the minimum requirement of a city's civil service system is "the mere establishment of minimum standards of employment and qualifications for the various classes of employment...."
If you have no job description, then it would be difficult to argue that the qualifications for your job classification are established. Consequently, the lack of a job description would violate the minimum requirements of California law.
The problem for you is the even though the lack of a job description is almost certainly a violation of law, the issue of compensation is controlled by the city's civil service ordinance. I have examined the online version of the Fairfield City Code and I find no classified employment/civil service ordinance. I find job requirements and compensation descriptions for the mayor, city manager, and city attorney -- but nothing else. Consequently, unless you can provide me with a link to the relevant city classified employment ordinance, then my answer must be that there is no civil service system established in Fairfield -- so, there are no requirements concerning job descriptions or compensation -- with the exceptions that I have identified.
It's actually a bit odd. The city population is greater than 100,000, so I would expect some sort of civil service ordinance. But, if it exists, it has not been included in the city code. This may in fact be true -- employers like to "hide the ball," as I'm sure you're aware. You're in a better position than I am, to try to uncover the city's civil service ordinance. If it exists, and you can point me to it, I'll be happy to investigate further. But, at this point, I've reached the end of the road.
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