That is a question of state law, not U.S. immigration law. If it is allowed, you did not violate the immigration law.
The above is intended only as general information, and does not constitute legal advice. You must speak with an attorney to discuss your individual case.
Not an immigration question. This is a matter of state and local law.
(213) 394-4554 x0 Mr. Shusterman is a former INS Trial Attorney (1976-82) with over 35 years of immigration experience. His response to your question is general in nature, as not all the facts are known to him. You should retain an attorney experienced in immigration law to review all the facts in your case in order to receive advice specific to your case. Mr. Shusterman's statement above does not create an attorney/client relationship.
Normally you would not be able to vote on local or states issues if you are not a citizen, but you should have an immigration lawyer take a look in your jurisdiction to see if there are any states laws that permit non-citizens to vote in that jurisdiction. The penalties are very harsh if you voted without being allowed to do so.
In WA, a person has to be a US citizen to vote in any public election whether it is for a federal, state, or local issue. See the information provided by the Secretary of State at https://wei.sos.wa.gov/agency/osos/en/voters/Pages/voter_eligibility.aspx .
To register to vote in WA, the applicant must declare on oath that the person is a citizen of the US.
You need to review your specific facts with your attorney to find out your legal options. Claiming one is a US citizen when one is not a US citizen is generally a basis for the US government to deport the claimant from the US.