HOUSTON (CN) - Texas Sen. Ted Cruz is not eligible to become president because he was born in Canada, a Houston lawyer claims in a federal class action.
Cruz is the favorite to win the Republican presidential candidate nomination at the Iowa caucuses on Feb 1. ahead of Donald Trump, according to a recent poll by the Des Moines Register.
Rafael Edward "Ted" Cruz was born Dec. 22, 1970, in Calgary, Canada, to an American mother and a Cuban father.
His origins have stirred controversy on the campaign trail with Trump claiming there are legitimate questions about whether his Canadian birth disqualifies him from being president or vice president of the United States.
Cruz scoffed at that idea on Thursday during a GOP presidential candidate debate in South Carolina.
"I recognize that Donald is dismayed that his poll numbers are falling in Iowa. But the facts and the law here are really quite clear. Under longstanding U.S. law, the child of a U.S. citizen born abroad is a natural-born citizen," Cruz said.
That's why Sen. John McCain, R-Ariz., who was born in Panama, could run for president in 2008, Cruz said during the debate.
Houston attorney Newton Boris Schwartz Sr., 81, isn't so sure about Cruz's candidacy.
Schwartz says the U.S. Constitution is unclear on the question of Cruz's eligibility in a lawsuit he filed against Cruz on Thursday in Federal Court in Cruz's hometown of Houston.
Schwartz claims in the lawsuit there is no U.S. Supreme Court precedent to determine if Cruz qualifies.
"'Natural born citizen' has never been defined," the complaint states.
Schwartz says his status as an eligible voter for the Nov. 1 presidential election gives him standing to bring the lawsuit.
He seeks a declaration that Cruz is not "a 'natural born' citizen" and is "therefore ineligible to be elected, or serve as president or vice president of the U. S."
Schwartz said he's voted for a Democrat in every presidential election since 1968 when he voted for Richard Nixon, a Republican, except in 1992 when he voted for Texas billionaire Ross Perot, who ran as an independent.
"If I had to vote on who the candidates are now I would probably vote for Bernie Sanders. My wife is leaning toward Hillary Clinton," he said in a phone interview.
Schwartz has practiced law for 61 years, including three years as a federal prosecutor in Houston and two years as a U.S. Air Force JAG officer, he said.
He said he expects his case will lose before a trial court and the Fifth Circuit Court of Appeals in New Orleans, then move on to the Supreme Court where he expects it to "go 5-to-4 or 6-to-3 either way, so it's going to be an uphill fight."
"This is a serious and substantial question. I'm trying to get it heard as quickly as we can to avoid a futile election. If Trump puts Cruz as his vice president even and he's later found disqualified, what do you do? You have to go back and have a new election for president or vice president," Schwartz said.
Trump said during Thursday's debate that he's simply repeating what others have said about Cruz's presidential eligibility, including Cruz's former Harvard Law School professor Laurence Tribe.
"There are other attorneys that feel, and very, very fine constitutional attorneys, that feel that because he was not born on the land, he cannot run for office," Trump said.
"Here's the problem. We're running. We're running. He does great. I win. I choose him as my vice presidential candidate, and the Democrats sue because we can't take him along for the ride," Trump added. "I don't like that. OK?"
Cruz said he's not worried about Trump's rhetoric at Thursday's presidential debate. Cruz is a Harvard-trained lawyer and served as Texas' solicitor general from 2003 to 2008, a job that required him to present legal arguments for the state before the U.S. Supreme Court.
"I've spent my entire life defending the Constitution before the U.S. Supreme Court. And I'll tell you, I'm not going to be taking legal advice from Donald Trump," Cruz said.
He also downplayed a recent New York Times article that reported he didn't disclose $1 million in loans he took out to finance his 2012 U.S. Senate campaign, including a $500,000 loan from Goldman Sachs, his wife Heidi's employer.
"I made a paperwork error," Cruz admitted. He said he disclosed the loans on personal financial disclosures he filed with the U.S. Senate, but erred by not disclosing them in reports made to the Federal Election Commission.
President Obama's presidency has been dogged by a similar "birther" conspiracy theory that contends he is an illegitimate president because he was born in Kenya, his father's homeland, not in Hawaii like his birth certificate says.
Trump has been a vocal critic of Obama and has questioned the authenticity of the president's birth certificate.
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