The fine for failing to initially register your vehicle in Washington is $1,100. It is fairly easy for a police officer to determine you have been living here for more than 30 days. If an officer believes you are intentionally keeping your vehicle registered out of state you could be charged criminally
How do they know when you moved here? They have no idea of when you moved here unless you tell them. For all they know, you moved here last week. Maybe you just got your car here from your old house or town. I don't know the cost of the fine. Whatever you decide, they're not going to question you.
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