SAN DIEGO (AP) — A man who was denied permission to return to the United States from Mexico sued the federal government Tuesday, saying he was misled by a little-known benefit aimed at keeping married couples together in the U.S. while a spouse waits for a green card.

Marco Villada, who came to the U.S. from Mexico when he was 6 years old, got permission from U.S. Citizenship and Immigration Services to leave the country for a green card interview at the U.S. consulate in Ciudad Juarez, Mexico. The waiver would let him quickly return to the U.S., avoiding the long wait in Mexico that others face.

The State Department permanently barred Villada from the United States after a visit to Mexico for his grandfather's funeral in 2000 came up during the green card interview, according to the lawsuit. Villada had told Citizenship and Immigration Services about the visit before obtaining the waiver.

Citizenship and Immigration Services didn't tell Villada that his Mexico visit in 2000 might damage his case, the lawsuit said. It gave other reasons he might not be allowed to return in "confusing, boilerplate" language.

"We did everything by the book," Villada said from Mexico on a conference call with reporters. "We thought that since we had the waiver nothing could go wrong but that wasn't the case."

The State Department and Citizenship and Immigration Services wouldn't comment on pending litigation.

Villada, 34, worked as a legal assistant in a Los Angeles-area law firm after qualifying in 2013 for the Deferred Action for Childhood Arrivals program, which has temporarily shielded hundreds of thousands of young people from deportation and given them work permits. By going to Mexico for his green card interview, Villada lost DACA protection because the program prohibits leaving the United States.

He wed Israel Serrato, a U.S. citizen, in 2014, months after gay marriage became legal across the United States. Serrato, also a plaintiff, joined his spouse for the trip to Mexico and has returned to the United States.

"Our hearts shattered (when the green card was denied)," Serrato told reporters. "One of our deepest fears came true. Marco is now stuck in the wrong country, away from me, away from the rest of our family, friends."

Under federal law, spouses are barred from returning for 10 years if they had been in the U.S. illegally for a year or more, but the Citizenship and Immigration Service waivers shorten the wait in cases of "extreme hardship." In 2013, the agency allowed people to obtain waivers before leaving the United States instead of having to wait months aboard for one.

Stacy Tolchin, Villada's attorney, said the waivers allow spouses to return to the U.S. when their visas are approved and typically go back to their native countries within two or three weeks to pick up the documents.

The number of people who got waivers and were later denied a visa is unknown, but Tolchin says her office has fielded calls from about six others.

"This is a problem that's been very frequent since the change of administrations," she said. "This is part of a larger problem."