IN THREE DAYS of public hearings on the question of continuing rent control in the District, dozens of tenants and labor union officials said that ending rent control would allow landlords to demand huge rent increases.

But officials from neighboring Montgomery County, where rent control has been abolished, testified in the same hearings that only 5 percent of the county's landlords applied for "extraordinary rent increases." Here and in New York City, they testified, rent control has helped the rich, not the poor.

In New York City, said Peter Salins, chairman of the urban affairs department of Hunter College, "the richer you are, the more you benefit" from rent control. Affluent tenants pay about 15 percent of their salary for their rent-controlled apartments, while the poor pay 40 percent or more of theirs. Rent regulation, Mr. Salins said, discourages the building of new apartments and the maintenance of old ones.

Anthony Downs of the Brookings Institution said that the federal government should be responsible for helping the poor get better housing. But because that is unlikely, he said, he prefers D.C. Council member John Ray's "phase out" rent control bill to the existing law. Rent control, Mr. Downs said, "is an unfair attempt to deal with poverty by forcing one group (landlords) to subsidize another group (tenants.)"

Mr. Downs said that Mr. Ray's bill, which advocates abolishing rent control from vacated apartments, could lead to a considerable amount of renovation and to the restoration of some of the city's vacant apartment buildings. He warned, however, that the $15 million Mr. Ray proposes in order to supplement the income of tenants would not be nearly enough.

Mr. Salins supported "housing vouchers," a rent assistance program piloted in some cities during the Nixon and Carter administrations: funds would be given to landlords to make improvements or pocketed by tenants to make their own improvements. Mr. Downs said that the decontrol of vacant apartments is necessary to spur the market for rental properties.

One of the chief responsibilities of any city is to help provide decent housing for those truly in need. In the District, these people have been shortchanged.