Salvadoran immigrant Adelia Aguilar, center, might be eligible for a green card as a result of President Obama's executive action on immigration. She is pictured in her Manassas apartment with her two U.S.-born teenage children, John and Alba. (Sarah L. Voisin/The Washington Post)

A little-known provision of U.S. immigration law, which allows illegal immigrants to travel home in special or emergency circumstances, is being denounced by Republican critics and others as part of a back-door scheme by the Obama administration to slip large numbers of illegal immigrants into line for green cards and U.S. citizenship.

The special travel permission, known as “advance parole,” is one of the benefits that as many as 5 million undocumented immigrants could apply for under the president’s executive action offering a three-year reprieve from deportation.

The use of advance parole, as well as other elements of the Obama administration’s plan, represents a “sneaky attempt to place potentially hundreds of thousands of unlawful immigrants on a path to citizenship,” charged Rep. Bob Goodlatte (R-Va.), a persistent critic of Obama’s immigration policies who chairs the House Judiciary Committee.

But is there any truth to Republican criticisms? Yes and no, it appears.

What even many illegal immigrants don’t know is that taking an approved trip home and back has a magic side effect: It erases the legal black mark of the person’s original illegal border-crossing — known as Entry Without Inspection, or EWI — and thus eliminates a major barrier to becoming a legal resident.

Salvadoran immigrant Adelia Aguilar, center, with her two U.S.-born children, John and Alba. (Sarah L. Voisin/The Washington Post)

But immigration officials and advocates say that Goodlatte’s numbers probably are exaggerated because green-card applicants need an American sponsor, usually a spouse or an employer, and must meet other qualifications, including having a clean criminal record. Traveling with advance parole does not change any of that.

“It won’t fix fraud, and it won’t fix not having a sponsor,” said John Y. Vandenberg, an immigration lawyer in Philadelphia who has written extensively on the subject. “It merely provides a remedy for a specific different problem — one that is standing between families being permanently united or potentially separated.”

For the moment, the issue is moot because of a lawsuit challenging Obama’s legal right to take broad executive action to benefit millions of illegal immigrants. A federal judge has suspended the deferred deportation actions, and the administration has asked for an emergency stay of the order while higher courts decide the case.

But Obama’s policy may well be cleared to resume later this year, making the issue of advance parole timely and significant for illegal immigrants targeted by the president’s action who are either parents of U.S.-born children or adults who immigrated illegally as children. This is especially true for those married to U.S. citizens, who potentially stand to gain much more than a work permit and a trip to their home village in Mexico or Central America.

For many illegal immigrants, the chance to legally travel home and back, often for the first time in years, is one of the most eagerly awaited elements of Obama’s plan.

According to government statistics, of the 522,000 young illegal immigrants who were awarded deportation relief through a 2012 presidential order called Deferred Action for Childhood Arrivals, or DACA, only about 6,400 applied for advance parole. But most of those applications were granted — a fact that alarmed Goodlatte and other critics.

This time, the government has invited all applicants to request advance parole at the same time they apply for the newly extended version of DACA, and far more are expected to do so.

Salvadoran immigrant Adelia Aguilar, 54, might be eligible for a green card as a result of President Barack Obama's executive action on immigration. She is pictured in her Manassas apartment. (Sarah L. Voisin/The Washington Post)

Moreover, the number of illegal immigrants who are parents of U.S. citizen children, covered in a separate White House executive action called Deferred Action for Parents of Americans, is much larger with potentially deeper ties to home countries.

In some cases, these immigrants, too, will be able to use approved home travel as a means to “cure” their original illegal entry — often several decades earlier — and apply for permanent residency.

This extra method of overcoming barriers to legalization is not widely known and has evolved recently through a series of court rulings and changes in the law.

At one time, illegal immigrants who left the United States were automatically barred from returning for three or 10 years, depending on how long they had lived here. This situation often led to agonizing personal choices, such as whether to risk visiting a dying parent.

But in 2012, an immigration court ruled that advance parole should not count against an immigrant’s need to maintain a full-time “lawful presence” in the United States in order to apply for a green card. The judge’s ruling “shook the earth,” Vandenberg wrote.

That year, when Obama issued his first DACA order, word began to spread about the potential extra benefit of obtaining advance parole. Vandenberg, who published a paper on the issue last year, was flooded with excited messages such as this one, from an immigrant named Jessica: “I just received DACA and I had no idea I was able to apply for advance parole. . . . I saw that parole can cure EWI. Is that true? If so can I adjust my status through my husband? We have been married for 2 years.”

In the Washington area, immigration advocates said they view advance parole as a godsend for families that have members in the country legally and illegally. At Just Neighbors, a nonprofit program in Northern Virginia, attorney Allison Rutland Soulen said advance parole is neither a “magic wand” nor a “back door” for her clients, but rather a legal way to resolve cases where the sole impediment to permanent residency is a border-crossing that took place many years ago.

One such client is Adelia Aguilar, 55, a Salvadoran health-care worker in Manassas, Va., who fled her conflicted homeland 21 years ago. She has two teenage children who were born in the United States, and she has temporary protected legal status as a war refu­gee. Last year, she was granted advance parole to attend the funeral of her father, whom she had supported for years without being able to see him.

Recently, Aguilar learned from Soulen that the approved funeral trip she took will “cure” the illegal border-crossing she made 21 years ago — and thus enable her son John, now 19, to sponsor her for a green card once he is 21.

“I have worked for a long time, and America has given me many opportunities, but it also took away a lot,” Aguilar said. “Here I am caring for elderly people, but I would have given anything to be with my father and care for him in his last days. It’s too late for that prayer to be answered, but maybe now God is helping me in another way.”

Immigration officials caution that to obtain advance parole, illegal immigrants must prove they have a bona fide family emergency or an educational or professional purpose for travel. They also note that those who abuse advance parole, by overstaying their trips and trying to return illegally, will again be subject to deportation.

To critics, though, the use of advance parole to erase the offense of an earlier illegal entry is a gimmick that flouts the basic intent of immigration laws and part of a pattern by sympathetic officials to expand the ways illegal immigrants can become legal in the absence of comprehensive immigration reform.

“This is one more example of the anti-border folks pushing in every direction to get more people legalized,” said Mark Krikorian, executive director of the Center for Immigration Studies in the District. “I am for amnesty in some cases, but this is chipping away at various restrictions to get more and more amnesty here and there.”