"Government agencies who serve low-income women need to be more cognizant of sex harassment and incorporate it in the way they deal with landlords," she said.
It is difficult to definitively know how many women are being harassed at home because it often goes unreported. Figures of reported incidents are also difficult to come by because women have a variety of private, state and federal agencies to tell.
Of the 10,000 discrimination in housing complaints the Department of Housing and Urban Development received last year, about 10 percent, or 996 cases, pertained to sex discrimination, said Kim Kendrick, a fair housing and equal opportunity official at HUD. HUD does not, however, distinguish between traditional forms of discrimination and harassment.
Of the 24 sex discrimination in housing suits the Department of Justice has brought against landlords in federal courts since 2001, two-thirds of them related to sexual harassment.
The Justice Department does not prosecute every instance of harassment in housing and will only take a case when a significant number of tenants report abuse.
Though women can report harassment to a variety of agencies -- including local fair housing organizations, HUD or their caseworkers if they receive government assistance -- they rarely do.
"Women are likely to get away quickly," Houk said. "They'll break the lease and move rather than report."
"Women who use [government assistance] vouchers or live in rent-stabilized apartments will try to add locks, get a male roommate, or change routines to avoid running into the manager. … The last thing done is complain, in part because no one else is around to see it. … There's a burden on women to prove this happened, and they worry about 'How will I prove it?'"
According to Rigel Oliveri, a law professor at the University of Missouri and a former civil rights lawyer at the Justice Department, some women also don't report harassment because they do not know it is illegal.
"Women realize it's wrong but don't know it's illegal. They don't think they can call the police because they think it's a landlord-tenant problem and don't realize it's a civil rights violation," Oliveri said.
The fact that it is a civil rights issue is at the heart of the matter for the federal government.
"The Fair Housing Act protects against discrimination on the basis of race, national origin and gender. Harassment is an egregious form of discrimination and no woman should be discriminated in her home," said a senior Justice Department official on the condition of anonymity.
In determining cases, courts often look to see whether landlords have created a "sexually hostile living environment." That environment could be created as early as the first time a potential tenant comes to look at apartment.
"This kind of conduct is on a broad spectrum. … Sometimes when a tenant comes applying to rent, a landlord offers a reduction in rent for sexual favors … making a quid pro quo offer," Houk said.
As in Mary's case, it is not uncommon for landlords to harass multiple women over the course of several years.
In one of the most often cited cases in recent years, U.S. vs. Veal, Bobby Veal of Kansas City, Mo., was found to have violated the Fair Housing Act when he demanded sexual favors from 11 tenants and evicted tenants who did not submit to his advances.