What you have there is a bogus sovereign citizen plate. Sovereign citizenship is a conspiracy theory that is running rampant in the US right now where crackpots think they do not have to abide by the laws set forth by the government. They do things like not register their vehicles, don't pay property/income tax and resist police officers who inevitably pull them over.
It's based on complete nonsense and these fools end up in prison and have their vehicles impounded time and time again. You can find many videos on YouTube of these guys getting taken down by police and subsequently arrested. It's very satisfying.