Mayor Marion Barry's administration urged the D.C. City Council yesterday to adopt legislation requiring all passengers of motor vehicles driven in the District to wear seat belts -- a proposal that was defeated this year in the Virginia and Maryland legislatures.

Council member Wilhelmina J. Rolark (D-Ward 8) has introduced a bill requiring the driver, front-seat passengers and anybody in the back seat under the age of 18 to wear a seat belt while parked or riding in a motor vehicle.

However, representatives of the administration and several special interest groups who testified yesterday at a hearing before the council's Public Works Committee argued that the bill was inadequate because it didn't apply to nonresidents and because it includes weak penalties and enforcement provisions.

While Rolark's bill "would make the use of safety belt systems mandatory in most instances, it does not go far enough in the interest of public safety," said Robert O.D. Thompson, head of the D.C. Transportation Systems Administraton, who testified for the administration.

For instance, under the proposed measure police officers would be instructed not to stop a vehicle in which a passenger was not using his seat belt unless there was probable cause to believe that the driver had committed some other offense.

The bill would impose a maximum fine of $25 and drivers who violated the law would not have "points" added to their record.

Rolark said after the meeting that there was considerable support among her colleagues for some type of seat belt legislation and that she was willing to go along with some of the changes sought by the administration and others.

However, Council Chairman David A. Clarke, who did not attend the hearing, said he opposed the concept of mandatory seat belt use legislation for adults and that he would vote against he bill if it is brought before the full council.

Council member Nadine P. Winter (D-Ward 6), chairman of the Public Works Committee, raised concerns during the hearing that a mandatory seat belt law would be difficult to enforce and might prove to be unfair or daunting to persons visiting from states that don't have similar laws. "This is a tourist town," she said.

Last January, New York became the first state to begin enforcing mandatory seat belt use legislation. Ten other states have adopted similar legislation: New Jersey, Illinois, Michigan, Missouri, Indiana, New Mexico, Hawaii, Texas, North Carolina and Connecticut.

Virginia and Maryland lawmakers rejected mandatory seat belt use bills this year, partly because of strong opposition from a coalition of conservatives and civil libertarians.

Proponents contend that enactment of seat belt legislation would save 440 lives each year in the District, Virginia and Maryland and would also prevent 11,900 serious injuries.

However, some groups have mixed feelings about pushing too hard for state mandatory seat belt laws, for fear of undermining the U.S. Department of Transportation's plan to gradually force automobile manufacturers to install airbags and other "passive-restraint" safety devices in all new cars.

By 1990, all new cars must contain the safety devices. However, this requirement would be rescinded if state legislatures representing two-thirds of the U.S. population enact and enforce mandatory seat belt use laws by 1989.