STEVE DOOCY: The state of California has passed legislation that will automatically register eligible voters when they obtain or renew a driver's license. Governor Jerry Brown says it's a way to increase voter turnout, but critics warn the measure could add millions of illegal people to the rolls because the state allows undocumented aliens to get driver's licenses. That's a problem, isn't it, Judge Napolitano?

ANDREW NAPOLITANO: Yes, yes. Good morning, Steve. Yes, it is a problem because the other states, including our own home state of New Jersey, which permit registration at the time you get a driver's license, have you go through another procedure in which you have to demonstrate citizenship.

DOOCY: You've got to prove you're here legally.

NAPOLITANO: Correct, correct. California, it's one procedure. You may not even know that when you get your driver's license you're also being registered to vote. And there's no requirement of proof of citizenship. What's the significance of proof of citizenship? All 50 states limit voting to citizens except when the state allows you to sort-of sneak in without proving your citizenship by getting a driver's license instead.

DOOCY: Sure. And one of the things they'd look to is the Supreme Court in the past has said that the right to drive in the United States is fundamental. However, they don't say you have to be an American citizen, per se. But what about the right to vote?

NAPOLITANO: You know, there's a lot of debate without getting too academic about what the right to vote is. Is it a fundamental right that comes from our humanity like thought and speech and association and worship and self-defense? Or is it a privilege given by the government? In my view, the Supreme Court has wrongly said it's a fundamental right. And once it said that, states like California decided to allow people to vote who aren't qualified by law to vote because of the fundamental aspect.

DOOCY: Those are for state elections.

NAPOLITANO: For any election in California.

DOOCY: But it's against the law on federal elections?

NAPOLITANO: Yes, it is. But there's really no way to monitor it. So if you are an illegal alien in California, get a driver's license, register to vote, you can vote in local, state, and federal elections in California and those votes count.

DOOCY: Interesting stuff.

NAPOLITANO: It's almost impossible to monitor this if the state is going to provide shelter for illegals to vote.

DOOCY: And so that's what is going to happen out in California.