My advice is restricted to advice surrounding the general principles of law governing your issue and you should not act on this advice but seek further clarification from a specialist in your County.
Your exclusion from the Board is not based upon any suspect classification, that is not your race, age, gender, religious views. Hence, a municipal authority may exclude those people if the exclusion is rationally related to its objective.
Here it's objective is to ensure that there are no conflicts of interest between paying customers and they duties of board members to the the utility company.
Hence, I don't really see what you can do here absence a showing of arbitrary discrimination its practice of exclusion seems to fit its purpose.
Please discuss this further with a local Attorney.
Thank You for your question.
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