Ozier Muhammad/The New York Times Martina Okeke, 68, says that she was fooled into coming to America as a servant by a family on Staten Island that refused for 12 years to pay her.

April 24, 2007—Martina Okeke lives in a dark basement in Queens that reeks of some mystery odor. She earns $100 a week caring for a cherubic toddler. She ekes out a few more dollars pushing a battered shopping cart through the streets of South Jamaica, filling it with cans and bottles she plucks from the garbage and cashes in for the deposits.

Welcome to America.

“It’s not easy,” she said with a shrug. “Yeah, but what can I do?”

She is used to doing whatever she must to survive. Born 68 years ago in Nigeria, she has been a seamstress, a trader and even a farmer. She said that in 1988, widowed and with two children to support, she agreed to come to the United States to cook, clean and care for the children of a Nigerian couple living in Staten Island. She said they promised to pay her $300 a month. There were promises of a house and tuition, she added, for her two children back home.

Ozier Muhammad/The New York Times Beatrice Okezie, 30, spent nine years enslaved by a Bronx couple, who were convicted on federal charges. She now helps similar victims.

She admits now that she toiled 12 years for a paycheck that never came. Not one cent.

Encouraged by friends from her church, she worked up the courage to leave the family in 2000. Still, she refused to report the family to the authorities.

“I did not want to have a bad name,” she said, in the basement that is her home in freedom. “That somebody took me from Nigeria to America and I made trouble for them. I know my people. They would say I went to America to make trouble. That would not be good for me.”

Fear keeps victims of human trafficking in shadows.

This is not uncommon, said advocates for victims of human trafficking. Fear, uncertainty and cultural taboos make it hard for women like Ms. Okeke to speak out. Although human trafficking has been a federal crime since 2000, efforts in the New York State Assembly to criminalize human trafficking and provide services for its victims have yet to succeed while advocates and politicians struggle to reconcile competing concerns over punishment and assistance.

“It’s amazing that we have not passed a law,” said Assemblyman Jeffrey Dinowitz, who started working on such a bill three years ago to enable local police departments and prosecutors to go after offenders. “For the most part, victims of human trafficking are not your typical poster child, so there is no urgency. And one of the biggest challenges is the victims are afraid to come forward, since there are so many burdens placed on them.”

Although politicians — especially at the federal level — inveigh against human trafficking as a crime that enslaves thousands of people, especially women forced into prostitution, policy experts said there were no reliable figures on the extent of the problem. The federal government cites a figure of up to 800,000 people being trafficked internationally, with more than 14,000 of those entering this country.

But those figures were criticized as flawed in a report issued last year by the Government Accountability Office, an investigative arm of Congress, which concluded that the government actually had no “effective mechanism” for estimating victims.

In what is believed to be the first effort of its kind in the nation, the nonprofit Vera Institute of Justice has begun a research project in New York City to develop better methods of identifying and counting victims of human trafficking.

In the absence of reliable figures, prosecutors and policy makers said, human trafficking is often cast in terms of the global sex trade, partly because there are more systematic methods like raids on brothels to root out its victims, as well as advocacy groups helping them.

“A lot of claims have been made by various agencies of the U.S. Government, lobbyists and activists that sex trafficking is the bigger problem, but there is no evidence to support that,” said one policy expert who spoke on condition of anonymity in order not to jeopardize relationships with advocacy groups and government officials. “And I am not sure that having the numbers will help the claims people have been trying to make.”

One federal prosecutor who has successfully brought cases against traffickers in the city said that people forced into labor as factory workers or domestic help might be more the norm than people would think. But they are also hard to root out because they are out of sight and isolated from the public.

Ms. Okeke said she spent her 12 years living in the basement of a house on a dead-end street on the north shore of Staten Island. In 1988, she said, a relative of Marco and Grace Mbadiwe approached her in her village with the promise of work in the United States. She accepted, expecting to be paid $300 a month.

What followed upon her arrival, she said, was two years of cooking, cleaning and baby-sitting without a day off. Only after she protested, she said, was she given Sundays off.

But no matter how many times she asked, she said, the Mbadiwes never paid her.

“They paid me nothing,” she said. “Every time I asked they said when I was ready to go back to Nigeria they would do something. I did not say anything against them. When I saw I received no pay, nothing, I told them, ‘I want to go, so pay me.’ They said I had to wait until I reached Nigeria.”

The Mbadiwes are divorced and did not respond to separate and repeated requests made in person, in writing and by phone for comment. Grace Mbadiwe, who now operates a day care center in her home, would reply only, “I have nothing to say about it” when asked in detail about Ms. Okeke’s claims.

Since leaving the family in 2000, Ms. Okeke has been helped with food and housing by a man from her village who gave her the basement apartment, which she shares with another woman. She has also sought immigration help from Africans in America, a group that was established six years ago to assist others who found themselves through force or fraud living in servitude.

Bonaventure Ezekwenna runs the group along with his wife, Beatrice Okezie, who herself spent nine years enslaved by a Bronx couple, who were eventually convicted on federal charges and sentenced to more than 10 years each. Through fliers and word of mouth, Africans in America tries to spread its message to others who may still be in servitude.

The group knows the lure of this country remains strong. “There is really crushing poverty back home, and everybody wants to run away from it,” Mr. Ezekwenna said. “When the trafficker comes, all he has to do is say they are taking them to America or Europe. That is synonymous with having a better life. How do you convince them? It is not hard.”

Ms. Okeke certainly found no golden door awaiting her when she arrived in this country. For now, she will settle for the battered gray metal door that leads to her basement home, where toddler toys clutter the room. She has not seen her own children — now adults — since 1988.

“They said they need my help,” she said of a recent letter from one of her children. “They are suffering.”

If she had the money, she would like to go visit them. Then she would come right back to New York, to the apartment where the cabinet doors hang off kilter, sunlight barely reaches and calendars teasingly depict smiling tykes and fetching women.

“This is rich compared to Nigeria,” she said. “Nigeria before was good. Now, it is like hellfire.”