Racial quotas in housing, which have divided the civil rights community and the housing industry bitterly and shattered traditional political alliances, drew equally divided opinions from experts during two days of hearings held this week before the U.S. Commission on Civil Rights.

When quotas are used in public housing, residents are selected from the waiting list in a manner that keeps the tenant population at a predetermined proportion of minorities and whites. Because most publicly assisted housing is heavily minority, the use of a quota means that blacks and other minorities on the lists often are skipped over and have to wait longer for housing than whites.

The Reagan administration regards quotas as illegal, William Bradford Reynolds, the Justice Department's assistant attorney general for civil rights, told the committee. "I can't conceive of a situation where I would exclude blacks who were interested in buying or renting a housing unit," he added.

John J. Knapp, general counsel for the Department of Housing and Urban Development, touched briefly on the subject in his testimony, saying only that some attempts to bring about racial balance "involve questions of whether some applicants will be admitted at all, or . . . when they will be admitted at all . . . ."

HUD has avoided making a decision on the quota issue in several instances, however. Tenant selection policies in use by public housing agencies in Montgomery County and Charlottesville, Va., have been awaiting action by HUD for a year and nearly two years, respectively.

Reynolds and Knapp were sworn in as witnesses, but others, whose discussions were called "consultations," were not sworn.

Advocates say that without quotas the pernicious discrimination that keeps many Americans living in segregated communities a generation after passage of the 1964 Civil Rights Act and 17 years after the passage of the Fair Housing Act of 1968 will never be eliminated.

Critics argue quotas are illegal and often hurt the people they are intended to help. "It seems to me that black families who have borne the burden of segregation now are required to bear the burden of integration" when quotas are used, said Mary Frances Berry, a member of the U.S. Commission on Civil Rights and a Howard University history and law professor.

After the 1968 housing act outlawed discrimination in the sale and rental of housing, the movement of black families into formerly white neighborhoods touched off flight by white residents when the percentage of blacks in the community reached a "tipping point," usually about 20 percent, according to Oscar Newman, director of the Institute for Community Design Analysis in Great Neck, N.Y.

To comply with the housing act and subsequent court decisions, the Department of Housing and Urban Development promulgated rules to give minority families access to publicly assisted housing, and foster construction of public housing outside the nation's ghettos, Newman said. But because HUD stopped short of using quotas, the federal agency's policies "resulted in housing developments turning predominantly black," he added.

As the public housing population became heavily minority, government and public support dropped off and funds dwindled, said Newman and other observers. Under the Reagan administration, the cutback of funds has curtailed housing assistance programs more dramatically than ever.

Some civil rights advocates shy away from quotas, putting their faith in the promise of the civil rights revolution of the 1960s that removal of institutional and legal barriers to discrimination and vigorous enforcement of anti-bias laws will lead eventually to an integrated society. Like former New York city housing commissioner Roger Starr, who appeared before the civil rights commission this week, many of these anti-discrimination advocates find quotas "repulsive."

Starr's major "quarrel" with quotas is that they mean "I have to look a black family in the eye and say I'm sorry, you're the wrong color" because the quota of minorities in a housing area has been reached, Starr said. "The progress of integration is going to be very slow," but in the long run, the most effective way to eliminate segregation will be enforcement of anti-discrimination laws. "This will be difficult but not so difficult as quotas," he said.

Housing desegregation "should mean free choice," giving people the ability to choose where they want to live, whether in predominantly white or predominantly minority neighborhoods, said Alexander Polikoff of Business and Professional People for the Public Interest. But blacks and whites who want to live in integrated neighborhoods find "that these neighborhoods don't exist in large numbers," he added.

The controversy over quotas has forged some unexpected alliances, according to Rodney A. Smolla, associate professor of law at the University of Arkansas. "There doesn't seem to be a consensus among Democrats or Republicans, or among conservatives or liberals, or even among ethnic groups as to how integration maintenance ought to be handled," he said.

"Most minorities like integration, but they also would like to have housing," Berry said.

The National Association for the Advancement of Colored People has opposed quotas in Charlottesville and in Starrett City, a state-owned public housing project of more than 5,800 units in New York. The NAACP and other civil rights groups sued, calling the tenant selection policy discriminatory.

Experts speaking before the civil rights commission also differed on the legality or illegality of housing occupancy controls.

Courts, however, have approved some quotas, said Newman.

"The courts have accepted that there might be a need to discriminate after a certain percentage of minorities have been served, in order to achieve and maintain stable integration -- that is, in order to avoid tipping . . . ," he said. But those using quotas have been required "to demonstrate that tipping would be the inevitable outcome should quotas not be employed."