The Internet may have opened new channels of communicating ideas to the masses, but it has also revealed that racism, sexism and homophobia are alive and well in cyberspace.

That’s changing.

Courts have held that persons posting defamatory content can be liable, and so can the Web site operator if it fails to remove such defamatory content after notice.

Now the courts are addressing whether the posting of discriminatory “classified ads” on Web sites is lawful.

A federal law immunizes Web sites when third parties post defamatory or discriminatory content. In other words, federal law sees Web sites as mere conduits of information, or “bulletin boards,” rather than as generating content/information, as newspapers do.

But in Fair Housing Council of San Diego v. Roommate.com, the United States Circuit Court of Appeals for the Ninth Circuit held that Web sites that facilitate discriminatory housing ads may be liable under federal and state law for doing so.

Federal law prohibits persons from engaging in housing bias based upon race, gender and religion. California law, in addition, prohibits bias based upon sexual orientation and gender identity. For example, it is illegal to publicly state, or advertise, “No gays or straights or lesbians or trans persons” when selecting a tenant or housemate.

Fair Housing Council of San Diego v. Roommate.com involves housing bias not generated but facilitated by Roommate.com: Roommate.com requires both those looking for rentals and those seeking tenants to answer questionnaires. A prospective tenant looking for a rental property can indicate whether he or she is straight or gay/lesbian, and the prospective landlord is similarly asked whether he/she wants “straight males only” or “gay males only” or “gay or straight” males. Roommate then categorizes and distributes the profiles based on the matches. The Web site has about 150,000 active listings and receives about a million page views per day.

The questionnaire feature is what separates Roommate.com from other Web sites, such as Craigslist, which simply post ads from third parties and function as a bulletin board, not a matchmaker.

The Appellate Court found that Roommate is not simply a facilitator or “passive” site. It engages in specifically asking questions that can produce discriminatory responses. Simply asking the question, “Would you rent to a gay person?” is discriminatory and, therefore, the court found that it is enough to cause the site to lose its immunity for damages.

It will be up to a lower court to determine whether this practice constitutes some form of aiding and abetting housing discrimination.

Dating/matching sites, of course, use gender, sexual orientation and religion to assess compatibility. But those are preferences expressed within the confines of personal, rather than commercial, relationships. It’s quite another issue to express such preferences for the purpose of housing, which federal, state and local laws regulate.

What’s interesting with the Fair Housing Council case is that one judge, Judge Stephen Reinhardt, known for being egalitarian on gay issues, would take the issue one step further. Reinhardt would also charge such sites with responsibility for the “open-comments” section on user profiles. This is where the user can write down anything, including discriminatory comments. In other words, even if the questionnaire didn’t request a preference, if the user states, “No gays” in an open-comment section, he would hold that, too, is discriminatory activity and the site would bear responsibility (at least once notified).

Web site owners want the law to treat them just like phone companies, where phone companies have no legal responsibility for defamatory or discriminatory content sent by callers. By contrast, print media is not just a facilitator of information; the courts charge publishers with exercising discretion.

Web site owners prefer the phone company model. However, most consumer advocates and civil rights supporters see the newspaper model as more appropriate.

Currently, which model applies depends upon the nature of the site. Fair Housing Council of San Diego v. Roommate.com puts Web site operators throughout the country on notice that allowing anti-gay “commercial” ads may subject them to liability in those states that offer protections against anti-gay discrimination.