The Supreme Court ruled Tuesday that Bellwood, Ill., and its residents have a legal right to sue real estate firms for alleged racial bias in sales practices. The ruling could make real estate firms nationwide significantly easier targets for lawsuits charging them with so-called racial steering.

Fearing a repeat of the pattern seen in Chicago of whole communities becoming black, one block at a time, the village of Bellwood, Ill., decided to take a stand on integration.

It was clear to both black and white residents alike that something had to be done, as reports reached the village hall of real estate brokers badgering home owners to sell before property values fell, according to Bellwood Mayor Sigel C. Davis.

It was also obvious, he said, that brokers were "steering" blacks toward the suburb, which is just west of Chicago, and encouraging whites to move elsewhere.

So. Bellwood-a community of more than 20,000 persons-passed a controversial fair housing ordinance designed to steady property values. It also required that information on listings be made available to everyone, regardless or race. The law required any one wishing to offer a home for sale to inform the village government and it barred brokers from soliciting listings without approval.

A community relations department was set up and an "affirmative marketing" program adopted in an effort to attract white buyers. The town, whose black population has grown to about 20 percent in the dozen years since the first black family moved in, also joined in several suits charging real estate firms with racial steering in violation of the Fair Housing Act of 1968.

Tuesday, Bellwood staved off one challenge from the real estate industry to its right to take steps to maintain an integrated community when the U.S. Supreme Court Ruled that municipalities have a legal right to sue brokers believed to practice racial steering.

(Another suit against the village, brought by the Illinois Association of Realtors, that challenges Bellwood's anti-solicitation and home sale notification laws is still pending.)

In a 7 to 2 decision that is being hailed by fair housing advocates as a major victory, the high court rejected the argument of two realty companies-sued by the village and several individuals in 1975-that only "direct victims" of alleged housing discrimination may file suit under the 1968 federal law. The ruling is expected to make it easier to attack housing discrimination in court because it eliminates the difficulty of locating individual victims of that discrimination.

"There can be no question about the importance to a community of promoting stable, racial integrated housing," Justice Lewis Powell wrote for the majority. "If, as alleged, sales practices actually have begun to rob Bellwood of its racial balance and stability, the village has standing to challenge the legality of that conduct."

Although the village sill faces a tough battle in U.S. District Court here, Mayor Davis said he was "delighted" by the court's ruling. Yet the village finds itself enmeshed in a broader controversy that has made strange bedfellows of the real estate industry and civil rights groups.

Real estate interests are expected to spare no resource in an attempt to prove in court that sales people are being harrassed for simply trying to do business. William D. North, general counsel for the National Association for Realtors, alleges that Bellwood and other suburbs like it that have enacted broad fair housing ordinances in an attempt to maintain racial balance are asking for a double standard.

"They would have us believe there are two types of steering-good steering and bad steering, depending on whether the white community feels there are too many or too few minorities," North said.

Meanwhile Bellwood is one of the Chicago suburbs that has come under fire from civil rights organizations charging that the fair fair housing ordinances are thinly disguised efforts to limit blacks' freedom of choice in housing and to establish racial quotas.

The position of the civil rights orgainzations signals a rift with the fair houseing movements, including such groups as Chicago's Leadership Council for Metropolitan Open Communities, an outgrouwth of Dr. Martin Luther King Jr.'s 1966 housing marches here.

A coalition comprised for Operation PUSH (People United to Save Humanity), the southside branch of the National Association for the Advancement of Colored People and the Chicago suburban chapter of the Souther Christian Leadership Conference has charged that under the guise of "integration maintenance" the communities are attempting to "manipulate the real estate market on the basis of race or ethnic group affiliation."

Tuesday's Supreme Court ruling was seen to have little effect on the situation. "Racial steering was always against the law, as we tried to emphasize-no matter who's doing it," commented Jean Oden, housing coordinator for the coalition.