The Supreme Court has decided to hear a challenge to Arizona's voter ID law, which requires people to show proof of citizenship in order to vote.

You would think that means voters in Arizona will

not be able to vote in three weeks without showing proof of U.S. citizenship. Not so fast, says Judge Andrew Napolitano, who pointed out on Happening Now that the law can be circumvented.

First off, the judge said you can get identification in Arizona without being a U.S. citizen and you can still actually register to vote without being a U.S. citizen, despite the state law.

"So here's the problem, if you show up to register at a polling facility — not on Election Day but in advance as the law requires — you will have to show proof of citizenship. But if you mail in a registration form, you do not have to show proof of citizenship. Why? Because the mail-in registration is regulated by a federal statute enacted in the Clinton years and the actual in-person registration is controlled by the state, which forces you to prove you're an American," said Napolitano.

Check out the rest of the judge's analysis here:

Check out more from Judge Napolitano:

AG Holder Has Given No 'Rational Basis' For Cracking Down on Pot Shops in California But Not in New Jersey

European Union's Nobel Peace Prize Win Is a 'Joke'

Florida School Standards Based on Race Are 'Unacceptable in Present Society'

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