When Steve Summers wanted to help his bride, Mexico-born Evangelina Zapata, obtain U.S. residency, he did what millions of other U.S. citizens to do to make it happen – he signed an affidavit vowing to support her so that she would not become a “public charge.”

In immigration parlance, a “public charge” is someone who relies on government assistance to pay for food and bills.

Now, after their divorce four years ago, the affidavit is being held up by Zapata in her push to get Summers to pay her alimony. She has sued Summers in federal court for breaking the contract to support her at 125 percent of the poverty level.

It is a contract, the lawsuit notes, that Summers entered into with her and the U.S. government, according to KGBT, a TV station in McAllen, Texas.

The lawsuit puts a spotlight on a part of immigration law – the I-864 affidavit – that, especially in divorce matters, rarely is enforced.  

Lawyers that specialize in immigration law, commonly seen as complicated if not more so than tax law, say they try to impress upon clients the serious responsibilities that come with signing an affidavit of support.

“We warn people about it,” said Joseph De Mott, an immigration lawyer in San Antonio, Texas, with nearly four decades of experience. “You don’t hear about it very often, it’s rarer that you hear about this being enforced. People sign these things, they go in a file and they just forget about it.”

Zapata's lawsuit calls for the petitioner to agree to support the immigrant at 125 percent of the federal poverty level unless the foreign national becomes a U.S. citizen, or works for roughly 10 years in a job through which they pay into the Social Security system, or fails to keep the permanent legal residency status.

“The premise is a good one,” Summers’ attorney, Marcus Barrera, told Fox News Latino. “If you’re going to sponsor someone to be a citizen, we don’t want to have to worry about that person, about you abandoning that person right away and wanting us to take care of them.”

But theory doesn't always make good practice, Barrera noted.

“But Summers is not in that situation,” he said. “They were married for many years, they have a child and she wanted a divorce.”

According to Zapata’s lawsuit, she arrived in the United States from Mexico in 2003, nearly a year after Summers petitioned for her to gain admission to this country through a “K visa,” also known as a fiancée visa. Summers filed the affidavit of support as part of the K visa application, the suit said. The suit said that the K visa covered her and “her children.”

The couple divorced in 2009. Zapata then remarried and divorced a second time.

Zapata contended that Summers never fulfilled the responsibility she said he agreed to in the affidavit, and said he is in violation of the Immigration and Nationality Act.

“Defendant’s failure to provide support to Plaintiff in accordance with the affidavit of support has caused financial damage to Plaintiff,” the suit said. “She has been unable to pay debts and [is] in jeopardy of losing her house and other assets.”

Barrera said that the law is flawed because it allows immigrants to languish indefinitely without working or becoming naturalized and they come to expect lifetime support from the U.S. citizen.

“They can stay for years in limbo status and never move out of it,” Barrera said, adding that an immigrant such as Zapata, who remarried and divorced, can come after the petitioner for support.

She and Summers have a young daughter. Barrera said his client was awarded custody of the child.

Summers is quoted by KGBT-TV as saying that he wants to see immigration reform tighten this provision of the law so that it cannot be exploited.

“The law is fairly ambiguous and I think there is some clarification that could be made,” he said, according to the website.

Proponents of strict immigration policies support the affidavit provision, saying the United States must ensure that immigrants do not end up being a social drain.

"Still, public charge doctrine remains one of America's fundamental immigration policies," wrote James R. Edwards Jr. in an essay for the Center for Immigration Studies website. "Immigrants turning to government programs at disproportionate rates tend to undermine public backing for mass immigration and lays the predicate for changing the immigrant flow."

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