I just found out that my ex husband is a registered voter in my states which implies that he received his citizenship. I filed I-360 petition based on my marriage to an LPR. Based on the laws, if he receives his citizenship my case also should be upgraded to the immediate relative category even after divorce. Would it be sufficient proof of his citizenship that he appears to be a registered voter? Obviously, I can't and won't ask him for his naturalization certificate. How should I proceed? Do I have to notify the Vermont Service Center where my original application went or the local office?
Any input would be appreciated.

If he is a classed as a registered voter, then he has to be a citizen to do so. Why do you want to report him ? What do you mean 'in my state(s)'?

Your question is oblique. We don't know what your purpose is.

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The purpose of my question is very clear for someone who is familiar with US immigration laws and knows what the difference are between an immediate relative and the preference categories.

So then explain what you want us to say, and please don't use the comments feature, use the reply feature, your question will receive more coverage that way if you don't like explaining what you want. And seeing as we are all volunteers here, you may have to wait a bit for a more qualified answer to your 'oblique' question.

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