Two questions: Did Ted Cruz's mother live in the U.S. for the required amount of time for him to have acquired U.S. citizenship? And can the Cruz family prove it??

Steven Lubet, a Northwestern University law professor, spies another possible land mine. Cruz qualified for citizenship because his mother was an American citizen (unlike his father). But "under the law in effect in 1970, Cruz would only have acquired U.S. citizenship if his mother had been 'physically present' in the United States for 10 years prior to his birth, including five years after she reached the age of 14," Lubet wrote in Salon.

That raises two questions: Did she live in this country for the required amount of time? And can the Cruz family prove it?

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